Vote shares that would have been needed to break select vote total records

(Italics indicate a record that actually was broken)

2020

Democrats

Nebraska (1932): > 37.73% (Biden actually did break this record with 39.36%)
North Dakota (1932): > 49.29% (actual: 31.76%)
South Dakota (1932): > 43.42% (actual: 35.61%)
New York (1964): > 57.02% (actual: 60.86%)
Rhode Island (1964): > 60.93% (actual: 59.38%)
West Virginia (1964): > 67.71% (actual: 29.69%)
Oklahoma (1976): > 34.12% (actual: 32.29%)
Arkansas (1992): > 41.49% (actual: 34.78%)
Louisiana (1996): > 43.19% (actual: 39.85%)
Indiana (2008): > 45.30% (actual: 40.96%)
Iowa (2008): > 49.02% (actual: 44.95%)
Michigan (2008): > 51.86% (actual: 50.62%)
Minnesota (2008): > 48.01% (Biden actually did break this record with 52.40%)
Missouri (2008): > 47.65% (actual: 41.41%)
Ohio (2008): > 49.64% (actual: 45.24%)
Pennsylvania (2008): > 47.38% (Biden actually did break the record with 50.01%)
Wisconsin (2008): > 50.85% (actual: 49.45%)
Wyoming (2008): > 29.94% (actual: 26.55%)

Republicans 

Iowa (1952): > 47.84% (actual: 53.10%)
Massachusetts (1956): > 38.37% (actual: 32.14%)
New York (1956): > 50.43% (actual: 37.73%)
Rhode Island (1956): > 43.61% (actual: 38.61%)
Illinois (1972): > 46.21% (actual: 40.55%)
Connecticut (1984): > 48.83% (actual: 39.21%)
Maine (1984): > 41.06% (actual: 44.02%)
New Jersey (1984): > 42.50% (actual: 41.40%)
Vermont (1984): > 36.98% (actual: 30.67%)
California (2004): > 31.48% (actual: 34.32%)
Maryland (2004): > 33.74% (actual: 32.15%)
Michigan (2004): > 41.77% (actual: 47.84%)
New Mexico (2004): > 40.79% (actual: 43.50%)
Ohio (2004): > 48.29% (actual: 53.27%)
Wisconsin (2004): > 44.82% (actual: 48.82%)
Alaska (2008): > 53.92% (actual: 52.83%)
Mississippi (2008): > 55.15% (actual: 57.60%)
Oklahoma (2008): > 61.52% (actual: 65.37%)
Idaho (2012): > 48.49% (actual: 63.84%)
Utah (2012): > 49.76% (actual: 58.13%)
Virginia (2012): > 40.86% (actual: 44.00%)
North Dakota (2016): > 59.92% (actual: 65.11%)
Tennessee (2016): > 49.87% (actual: 60.66%)
West Virginia (2016): > 61.58% (actual: 68.62%)

(The necessary percentage dropped dramatically in Iowa and Maine, but in neither state would Romney's vote share in 2012 have been sufficient. Likewise, it would have been hard, given the rise in turnout, for Trump not to set a new vote total record in Michigan and Wisconsin, but perhaps more impressive is that he did so even whilst Biden failed to do so for his party. Likewise in Ohio, although here, the percentage Trump needed was certainly one that he could have been envisioned falling below had the state returned to being a battleground, which Democrats certainly behaved as though was a possibility. Finally, Trump succeeded in resetting the Republican record in two slow-growing [or shrinking] states where he had broken a longstanding record just four years prior, and where Democrats have still failed to set a new record for over half a century: North Dakota and West Virginia. His falling below the necessary percentages, which could still have accompanied strong, landslide wins, could easily have been imagined in the climate of an overall generic Democratic year--Romney's vote share in North Dakota would not have been sufficient.

At the same time, the vote share necessary to break McCain's vote total record in Alaska fell below McCain's actual vote share for the first time; not only this, but it fell below 55%. And yet, Trump still failed to break this record in this generally solidly red state. Romney's vote share--while still somewhat alarmingly low--would, in 2020, have been sufficient to break this record.)

2016

Republicans

Iowa (1952): > 51.65% (actual: 51.15%)
West Virginia (1972): > 67.88% (actual: 68.50%) (Nixon's vote share: 63.61%)
Maine (1984): > 44.99% (actual: 44.87%)
California (2004): > 38.85% (actual: 31.62%)
Michigan (2004): > 48.21% (actual: 47.50%) (Bush's vote share: 47.81%)
Minnesota (2004): > 45.73% (actual: 44.92%)
New Mexico (2004): > 47.22% (actual: 40.04%)
Ohio (2004): > 51.65% (actual: 51.31%) (Bush's vote share: 50.81%)
Pennsylvania (2004): > 45.31% (actual: 48.18%)
Wisconsin (2004): > 49.67% (actual: 47.22%) (Bush's vote share: 49.32%)
Alabama (2008): > 59.65% (actual: 62.08%)
Alaska (2008): > 60.84% (actual: 51.28%) (McCain's vote share: 59.42%)
Mississippi (2008): > 59.92% (actual: 57.94%) (McCain's vote share: 56.18%)
Oklahoma (2008): > 66.08% (actual: 65.32%) (McCain's vote share: 65.65%)
Tennessee (2008): > 58.98% (actual: 60.72%) (McCain's vote share: 56.90%)
Arkansas (2012): > 57.29% (actual: 60.57%)
Arizona (2012): > 47.63% (actual: 48.08%)
Colorado (2012): > 42.63% (actual: 43.25%)
Georgia (2012): > 50.52% (actual: 50.77%)
Idaho (2012): > 60.98% (actual: 59.26%)
Kentucky (2012): > 56.50% (actual: 62.52%)
North Carolina (2012): > 47.88% (actual: 49.83%)
Utah (2012): > 65.46% (actual: 45.54%)
Virginia (2012): > 45.74% (actual: 44.41%)

(Trump could have been expected, at least in hindsight, to have set new records already in 2016 in Iowa, Maine, Michigan, Minnesota, Wisconsin, and even Ohio--again, in hindsight. While his performance in all these states turned out to be an upset, the fact that he didn't reach the vote shares necessary to become the top vote-getting Republican ever in those states may have been seen as revealing a slight softness in his performance, especially since Obama had done so for the Democratic Party in all those states in 2008.

Furthermore, the vote share Trump needed to break Romney's vote total record in Idaho was lower than McCain's; and, despite the early hubbub surrounding Trump's apparently strong showing in Virginia, he failed to get the vote share necessary to surpass Romney's vote total there either [which would still have entailed losing the state].

At the same time, Trump's breaking Nixon's vote total record in West Virginia was a significant accomplishment. The vote share necessary to do this was actually higher in 2012 than in 2004, but fell by over 3% in 2016 [although it was still higher than Nixon's actual vote share], reflecting that Trump not only got a very high vote share in the state, but also energised turnout in the state in a way Romney hadn't.

As after 2012, McCain remained the top Republican vote-getter ever in a surprising number of states, given the weakness of his national showing. In Oklahoma, Alaska, and Mississippi [the last of these, admittedly, one of the few shrinking states]--as well as in Tennessee, where Trump did break McCain's record--the vote share required to break McCain's vote total record was once again higher than the vote share McCain actually received--a somewhat strange phenomenon [as far as Oklahoma and Tennessee are concerned, certainly], given what happened in West Virginia.)

2012

Republicans

Massachusetts (1956): > 43.98% (actual: 37.51%)
West Virginia (1972): > 72.34% (actual: 62.30%) (Nixon's vote share: 63.61%)
North Dakota (1984): > 62.04% (actual: 58.32%)
California (2004): > 41.73% (actual: 37.12%)
Kansas (2004): > 63.69% (actual: 59.66%) (Bush's vote share: 62.00%)
Kentucky (2004): > 59.51% (actual: 60.49%)
New Mexico (2004): > 48.09% (actual: 42.84%)
South Dakota (2004): > 63.93% (actual: 57.89%) (Bush's vote share: 59.91%)
Alabama (2008): > 61.06% (actual: 60.55%) (McCain's vote share: 60.32%)
Alaska (2008): > 64.51% (actual: 54.80%) (McCain's vote share: 59.42%)
Arkansas (2008): > 59.66% (actual: 60.57%) (McCain's vote share: 58.72%)
Louisiana (2008): > 57.58% (actual: 57.78%)
Mississippi (2008): > 56.36% (actual: 55.29%) (McCain's vote share: 56.18%)
Oklahoma (2008): > 71.93% (actual: 66.77%) (McCain's vote share: 65.65%)
Tennessee (2008): > 60.16% (actual: 59.48%) (McCain's vote share: 56.90%)

(What Romney would have needed to get in Kansas and South Dakota was actually higher than what Bush actually got in those states [62.00% and 59.91%, respectively]. The same was true, obviously, vis-à-vis McCain in Alaska. 

Given that McCain was losing the national election quite badly, and Romney lost only narrowly, McCain maintained the GOP vote total record in a surprising number of states after the 2012 election. In all of them, the vote share Romney would have needed to break McCain's record was higher than what McCain actually got, indicating a large turnout for the Republican ticket in 2008 [or a dropoff in turnout for the Republican ticket in 2012]. [Indeed, this was even true in Arkansas, where Romney did manage to top McCain's vote total.] All of these states were in the South save Alaska.) 

2008

Democrats

Nebraska (1932): > 44.81% (actual: 41.60%)
North Dakota (1932): > 56.13% (actual: 44.50%)
South Dakota (1932): > 48.04% (actual: 44.75%)
Kansas (1936): > 37.50% (actual: 41.55%)
New York (1964): > 64.30% (actual: 62.88%)
Pennsylvania (1964): > 52.08% (actual: 54.49%)
Rhode Island (1964): > 66.87% (actual: 62.86%)
West Virginia (1964): > 75.42% (actual: 42.59%) (LBJ's vote share: 67.94%)
Oklahoma (1976): > 36.40% (actual: 34.35%)
Arkansas (1992): > 46.55% (actual: 38.86%)
Louisiana (1996): > 47.32% (actual: 39.93%)

Republicans

Alabama (2004): > 56.02% (actual: 60.32%)
Alaska (2004): > 58.52% (actual: 59.42%)
Arkansas (2004): > 52.72% (actual: 58.72%)
Kentucky (2004): > 58.55% (actual: 57.40%)
Louisiana (2004): > 56.21% (actual: 58.56%)
Mississippi (2004): > 53.10% (actual: 56.18%)
Oklahoma (2004): > 65.62% (actual: 65.65%) (Bush's '04 vote share: 65.57%)
Tennessee (2004): > 53.25% (actual: 56.90%)

(McCain set the Republican vote-total record in a surprisingly large number of states, given the magnitude of his national loss. Several were fast-growing, but the above are generally slow-growing, or, in any case, McCain's vote total record stood in them past 2012 [Alabama, Alaska, Mississippi, Oklahoma, Tennessee]. It appears that there may have been a surge in Republican turnout in several of these states in 2008, especially given the discrepancy in several of these states between Bush's vote share and the vote share McCain needed to overtake Bush's vote total [e.g., 56.02% vs. 62.46% in Alabama, 53.10% vs. 59.45% in Mississippi, 53.25% vs. 56.80% in Tennessee]. The dramatic nature of this apparent surge is further underscored by the difficulty Romney and in some cases Trump in 2016 had in surpassing McCain's vote total, despite [generally] getting higher vote shares. [Oklahoma, where McCain actually needed a higher vote share than Bush in '04 to set a new vote total record, was a conspicuous exception, although Romney and Trump still had difficulty surpassing McCain's vote total there.]

Kentucky was a somewhat odd anomaly within the 'Scots-Irish Zone'.

Alaska has generally not been a state in which it has been difficult for either major party to set new vote total records in; Walter Mondale set a record for his party in the state in 1984 [whereas it took much longer in many other states to break LBJ's vote total record], and it was one of the states where George W. Bush set the record for his party in 2000 [whereas it took until 2004 in many states]. But McCain's 2008 record will now have stood for a minimum of 16 years. Democrats, meanwhile, have reset their record in the state in 2004, 2008, and 2020.)

2004

Democrats

Kansas (1936): > 39.11% (actual: 36.62%)
Iowa (1964): > 48.64% (actual: 49.23%)
Ohio (1964): > 44.39% (actual: 48.71%)
Pennsylvania (1964): > 54.27% (actual: 50.92%)
Mississippi (1980): > 37.26% (actual: 39.76%)
Montana (1988): > 37.50% (actual: 38.56%)
Arkansas (1992): > 47.95% (actual: 44.55%)
Louisiana (1996): > 47.75% (actual: 42.22%)
Alabama (2000): > 36.77% (actual: 36.84%)

Republicans

Iowa (1952): > 53.68% (actual: 49.90%)
Pennsylvania (1972): > 47.05% (actual: 48.42%)
West Virginia (1972): > 64.16% (actual: 56.06%) (Nixon's vote share: 63.61%)
California (1984): > 44.01% (actual: 44.36%)
Connecticut (1984): > 56.43% (actual: 43.95%)
New Jersey (1984): > 53.54% (actual: 46.24%)
North Dakota (1984): > 64.04% (actual: 62.86%)
Vermont (1984): > 43.50% (actual: 38.80%)
New Hampshire (1988): > 41.54% (actual: 48.87%)

(In 2004, Bush failed to carry Pennsylvania but broke his party's record for most votes won in the state, whereas Kerry failed to do the same in the large swing state. As can be seen, it would have been considerably more difficult for Kerry to do so than for Bush, perhaps a reflection of the fact that LBJ's vote share in Pennsylvania [64.92%] had been non-trivially higher than Nixon's, eight years later [59.11%]. 

One particularly odd phenomenon is that Democrats broke their longest-standing vote total record in Iowa, a perennially slowly-growing state since the 1890s, considerably sooner than the Republicans did theirs: after 40 years vs. after 68. This, even though Iowa has drifted rightward and was already doing so when Kerry topped LBJ's vote total in 2004 [even as Bush became the first Republican to carry the state in 20 years]. As can be seen, Iowa was the reverse of Pennsylvania: the bar was substantially lower for the Democrats than for the Republicans. It's harder to explain why here; Eisenhower's 1952 vote share in Iowa [63.75%] was only slightly higher than LBJ's [61.88%], and was moreover twelve years earlier, when presumably the Iowa electorate would have been smaller--although actually, slightly more people voted in Iowa in 1952 than in 1964. 

Kerry only barely halted the Democracy's somewhat idiosyncratic runs of not improving its vote totals in Montana and, to a lesser extent, Mississippi. Kerry surpassed Gore's vote total in every state in which Gore set the vote total record for the party in 2000, but the closest Kerry came to not doing so was in Alabama, where Gore's vote share had been 41.57%.)

2000

Democrats

Iowa (1964): > 55.72% (actual: 48.54%)
Oklahoma (1976): > 43.14% (actual: 38.43%)
Michigan (1964): > 50.48% (actual: 51.28%)
Ohio (1964): > 53.09% (actual: 46.46%)
Pennsylvania (1964): > 63.73% (actual: 50.60%)
Mississippi (1980): > 43.18% (actual: 40.70%)
Montana (1988): > 41.10% (actual: 33.36%)

Republicans

Iowa (1952): > 61.49% (actual: 48.22%)
South Dakota (1952): > 64.46% (actual: 60.30%)
New York (1956): > 63.61% (actual: 35.22%) (Eisenhower's vote share: 61.24%)
Illinois (1972): > 58.80% (actual: 42.58%)
Indiana (1972): > 63.89% (actual: 56.65%)
Pennsylvania (1972): > 55.25% (actual: 46.43%)
West Virginia (1972): > 74.83% (actual: 51.92%) (Nixon's vote share: 63.61%)
California (1984): > 49.85% (actual: 41.65%)
Kansas (1984): > 63.17% (actual: 58.04%)
Louisiana (1984): > 58.75% (actual: 52.55%)
Michigan (1984): > 53.20% (actual: 46.15%)
Missouri (1984): > 53.99% (actual: 50.42%)
Nebraska (1984): > 66.00% (actual: 62.25%)
New Mexico (1984): > 51.30% (actual: 47.85%)
North Dakota (1984): > 69.50% (actual: 60.66%) (Reagan's vote share: 64.84%)
Ohio (1984): > 56.92% (actual: 49.97%)
Oklahoma (1984): > 69.80% (actual: 60.31%) (Reagan's vote share: 68.61%)
New Hampshire (1988): > 49.47% (actual: 48.07%)

(Given that New Mexico and New Hampshire had been traditionally Republican states, and the necessary vote share to set new vote total records in them was not that onerous in 2000, I might have seen Bush's failure to do so that year as ominous for the GOP in those states. However, Bush breaking Eisenhower's record in South Dakota, or Nixon's in Indiana--let alone Nixon's in Pennsylvania--in 2000 seems slightly unrealistic to have expected. No Republican this century has reached the vote shares in any of those states that would have been necessary in 2000. 

Al Gore beating LBJ's vote total in Michigan was certainly not something that could have been assumed, especially given that Michigan was thought to be a critical battleground state that year.) 

1996

Democrats

Nebraska (1932): > 53.01% (actual: 34.95%)
North Dakota (1932): > 66.95% (actual: 40.13%)
South Dakota (1932): > 56.67% (actual: 43.03%)
Kentucky (1964): > 48.22% (actual: 48.07%)
West Virginia (1964): > 84.54% (actual: 51.51%) (LBJ's vote share: 67.94%)
Oklahoma (1976): > 44.12% (actual: 40.45%)
Montana (1988): > 41.48% (actual: 41.23%)
Wisconsin (1988): > 51.31% (actual: 48.81%)
Arkansas (1992): > 57.20% (actual: 53.74%) (Clinton's '92 vote share: 53.21%)

Republicans

Alaska (1984): > 57.27% (actual: 50.80%)
Colorado (1984): > 54.40% (actual: 45.80%)
Florida (1984): > 51.48% (actual: 42.32%)
Idaho (1984): > 60.51% (actual: 52.18%)
Montana (1984): > 57.08% (actual: 44.11%)
North Carolina (1984): > 53.52% (actual: 48.73%)
South Carolina (1984): > 53.55% (actual: 49.89%)
Texas (1984): > 61.18% (actual: 48.76%)
Virginia (1984): > 55.33% (actual: 47.10%)
Utah (1984): > 70.48% (actual: 54.37%)
Arizona (1988): > 50.02% (actual: 44.29%)
Georgia (1988): > 47.03% (actual: 47.01%)
Nevada (1988): > 44.38% (actual: 42.91%)

(Bob Dole was one of just a handful of major-party nominees in the 20th and 21st centuries to fail to set his party's vote total record in a single state; he came closest in Georgia, and also came somewhat close in Nevada [despite not carrying the state], but otherwise fell far short in the fast-growing Republican-leaning states.)

1992

Democrats

Kansas (1936): > 40.14% (actual: 33.74%)
Kentucky (1964): > 44.86% (actual: 44.55%)
West Virginia (1964): > 78.70% (actual: 48.41%) (LBJ's vote share: 67.94%)
Alabama (1976): > 39.05% (actual: 40.88%)
Arkansas (1976): > 52.55% (actual: 53.21%)
Georgia (1976): > 42.20% (actual: 43.47%)
North Carolina (1976): > 35.51% (actual: 42.65%)
South Carolina (1976): > 37.49% (actual: 39.88%)
Tennessee (1976): > 41.66% (actual: 47.08%)
Mississippi (1980): > 44.84% (actual: 40.77%)
Texas (1988): > 38.23% (actual: 37.08%)

Republicans

Florida (1984): > 51.38% (actual: 40.89%)
North Carolina (1984): > 51.55% (actual: 43.44%)
South Carolina (1984): > 51.19% (actual: 48.02%)
Texas (1984): > 55.79% (actual: 40.56%)
Virginia (1984): > 52.26% (actual: 44.97%)
Arizona (1988): > 47.25% (actual: 38.47%)
Georgia (1988): > 46.59% (actual: 42.88%)
Nevada (1988): > 40.69% (actual: 34.73%)
New Hampshire (1988): > 52.41% (actual: 37.69%)

(Bill Clinton got more raw votes in Kansas, Kentucky, and Mississippi in 1992 than in 1996. Dukakis' vote share in Kansas would have been sufficient in 1992. Given the relatively low vote share necessary in '88 and '92, one might have thought that the record would have been broken in Kansas before 2008. 

Given that Clinton's national vote share was actually a relatively low 43.01%, and given how powerfully Carter had won many Southern states in 1976--getting over 55% in Alabama, Arkansas, Georgia, North and South Carolina, and Tennessee--one might not necessarily have expected Clinton to set new vote total records in the South. In his home state of Arkansas, he actually needed a majority; if it hadn't been his home state, Carter might well still own the Democratic record in Arkansas, as Arkansas was the only state in which Clinton got a majority in 1992. As it was, Clinton only barely edged Carter's record in Alabama, Arkansas, Georgia, and South Carolina. 

In Kentucky, where Carter himself had failed to top LBJ's vote total, Clinton fell just barely short twice.

Texas was a rapidly growing state in which Dukakis had gotten the most votes of any Democrat in 1988, which didn't happen in many Southern states. Clinton had hoped to win Texas, and until 1992, Texas had the reputation of the state without which Democrats could not win the White House, so it was odd that not only did Clinton fail to win the state, but he failed to get more votes than Dukakis.

Bush Sr's '92 candidacy became one of a handful of candidacies not to set any intra-party state-level vote total records; it appears he likely came closest in South Carolina, followed by Georgia, but didn't come particularly close anywhere else. Of the states where he himself had set the record in 1988, only in New Hampshire would he have needed to win a majority in 1992 to break his own record.)

1988

Democrats

South Dakota (1932): > 58.63% (actual: 46.51%)
Kansas (1936): > 46.78% (actual: 42.56%)
California (1964): > 42.20% (actual: 47.56%)
Iowa (1964): > 59.81% (actual: 54.71%)
Montana (1964): > 44.92% (actual: 46.20%)
Vermont (1964): > 44.44% (actual: 47.58%)
Louisiana (1980): > 43.51% (actual: 44.06%)

Republicans

Arizona (1984): > 58.15% (actual: 59.95%)
Florida (1984): > 63.46% (actual: 60.87%)
Georgia (1984): > 59.06% (actual: 59.75%)
Maryland (1984): > 51.33% (actual: 51.11%)
Nevada (1984): > 53.92% (actual: 58.86%)
New Hampshire (1984): > 59.28% (actual: 62.49%)
Virginia (1984): > 61.01% (actual: 59.74%)

1984

Democrats

Alaska (1964): > 21.35% (actual: 29.87%)
California (1964): > 43.89% (actual: 41.27%)
Colorado (1964): > 36.75% (actual: 35.12%)

Republicans

Iowa (1952): > 61.29% (actual: 53.27%)
South Dakota (1952): > 64.13% (actual: 63.00%)
New York (1956): > 63.84% (actual: 53.84%) (Eisenhower's vote share: 61.24%)
Illinois (1972): > 57.86% (actual: 56.17%)
Indiana (1972): > 62.92% (actual: 61.67%)
Pennsylvania (1972): > 56.03% (actual: 53.34%)

(Given that Reagan was winning a national landslide, his failure to break Nixon's records in the large Route 30 states of Illinois and Pennsylvania should perhaps have been somewhat worrisome and a portent of things to come, especially given that the vote shares he would have needed were not unreasonable for someone winning a 58.8% national landslide. Perhaps not coincidentally, Nixon in 1972 remained the last Republican to carry Cook County, Illinois and Allegheny County, Pennsylvania, and the last to get over 40% of the vote in Philadelphia County, Pennsylvania.)

1980

Republicans

Nebraska (1952): > 65.79% (actual: 65.53%)
California (1972): > 53.59% (actual: 52.69%)

1976

Democrats

Nebraska (1932): > 59.09% (actual: 38.46%)
North Dakota (1932): > 60.03% (actual: 45.80%)
South Dakota (1932): > 61.03% (actual: 48.91%)
Kansas (1936): > 48.50% (actual: 44.94%)
Mississippi (1952): > 22.43% (actual: 49.56%)
Alabama (1960): > 26.91% (actual: 55.73%)
Louisiana (1960): > 31.86% (actual: 51.73%)
Arkansas (1964): > 40.84% (actual: 64.94%)
California (1964): > 53.03% (actual: 47.57%)
Florida (1964): > 30.11% (actual: 51.93%)
Kentucky (1964): > 57.38% (actual: 52.75%)
Maryland (1964): > 51.03% (actual: 53.04%)
Missouri (1964): > 59.60% (actual: 51.10%)
Oklahoma (1964): > 47.59% (actual: 48.75%)
Tennessee (1964): > 43.01% (actual: 55.94%)
Texas (1964): > 40.85% (actual: 51.14%)
Virginia (1964): > 32.88% (actual: 47.96%)
West Virginia (1964): > 71.68% (actual: 58.07%) (Johnson's vote share: 67.94%)

(The primary determinants of whether Carter improved upon Lyndon Johnson's vote total in a given Southern state seem to have been whether Johnson overperformed or underperformed his national vote share in that state, and whether it was a fast-growing state or not. In Arkansas, Oklahoma, and Tennessee, while Johnson got more votes than any Democrat in history, he underperformed his national vote share in all three, getting 56.06%, 55.75%, and 55.50% in them, respectively. In these states, Carter set a new record for most votes won by a Democrat. On the other hand, he did not in Kentucky, Missouri, or West Virginia, where Johnson got 64.01%, 64.05%, and 67.94%, respectively [although in West Virginia Carter would actually have had to outdo LBJ's vote share]. In the rapidly-growing Southern states, Carter set a new record regardless of whether Johnson had underperformed in them [as in Florida and Virginia] or overperformed in them [as in Maryland and Texas]. 

In Kansas, again, Carter came close enough that one might have expected FDR's record there to be broken before 2008.)

Republicans

Alaska (1972): > 44.79% (actual: 57.90%)
Arizona (1972): > 54.23% (actual: 56.37%)
Colorado (1972): > 55.24% (actual: 54.05%)
Idaho (1972): > 58.48% (actual: 59.88%)
Montana (1972): > 55.97% (actual: 52.84%)
Nevada (1972): > 57.34% (actual: 50.17%)
Oregon (1972): > 47.26% (actual: 47.78%)
Utah (1972): > 59.80% (actual: 62.44%)
Wisconsin (1972): > 47.09% (actual: 47.83%)
Wyoming (1972): > 64.26% (actual: 59.30%)

1972

Democrats

Mississippi (1952): > 26.71% (actual: 19.63%)
Alabama (1960): > 31.64% (actual: 25.54%)
Louisiana (1960): > 38.74% (actual: 28.35%)
California (1964): > 49.86% (actual: 41.54%)

(California was a state in which LBJ underperformed his national vote share, McGovern overperformed his national vote share, and which was growing rapidly; but all these factors were not enough to give McGovern the record for his party in the state.)

Republicans

Illinois (1956): > 55.54% (actual: 59.03%)
Michigan (1956): > 49.10% (actual: 56.20%)
New York (1956): > 60.60% (actual: 58.54%)
New Jersey (1956): > 53.61% (actual: 61.57%)
Ohio (1956): > 55.26% (actual: 59.63%)
Pennsylvania (1956): > 56.30% (actual: 59.11%)

(Before the 1972 election, Eisenhower in 1956 held the record for most votes won by a Republican nominee in New York, Michigan, and all the Route 30 states. After 1972, he did so only in the now familiar clump of New York, Rhode Island, and Massachusetts [the only Northeastern states Dukakis would capture in 1988]. This could perhaps have been taken as a warning sign for the GOP, as New York was, at the time, considered a swing state, if perhaps one that leaned Democratic [Ford contested it in 1976]. At the same time, as one can see above, the bar was higher for Nixon in New York in 1972 than in any of the Route 30 states or Michigan, possibly an indication of a combination of relatively slow growth in New York compared to the other large industrial Frost Belt states and Eisenhower's exceptionally strong showing in the state in 1956--of the above listed states, Eisenhower broke 60% in 1956 only in New York, New Jersey, and Ohio, and underperformed his national 57.37% vote share in Michigan and Pennsylvania. [One can see from this also that Michigan, New Jersey, and Ohio, in particular, had not yet turned into the slow-growing states they are known as today--Eisenhower's actual '56 vote shares in the three had been 55.63%, 64.68%, and 61.11%, well in excess of what Nixon needed to get to match his vote total just sixteen years later, whereas Eisenhower's vote shares in New York and Pennsylvania had been 61.19% and and 56.49%, only slightly higher.])

1968

Democrats

Mississippi (1952): > 26.37% (actual: 23.02%)
Alabama (1960): > 30.32% (actual: 18.72%)
Louisiana (1960): > 37.12% (actual: 28.21%)

(These were the three states in which, after 1964, a Democrat other than FDR or LBJ held the intra-party raw vote total record. They afforded Humphrey perhaps the best chance for setting a state-level vote total record himself, even if he was doing quite poorly--and he came somewhat close in Mississippi.)

1964

Democrats

Iowa (1936): > 52.49% (actual: 61.88%)
Missouri (1936): > 61.12% (actual: 64.05%)
Montana (1936): > 57.31% (actual: 58.95%)
West Virginia (1936): > 63.45% (actual: 67.94%)
Mississippi (1952): > 42.18% (actual: 12.86%)
Alabama (1960): > 46.14% (actual: 30.55%)
Louisiana (1960): > 45.45% (actual: 43.19%)

(Percentage in Alabama is for unpledged Democratic electors; Lyndon Johnson was not on the ballot.)

1960

Democrats

Colorado (1936): > 40.07% (actual: 44.91%)
Illinois (1936): > 47.99% (actual: 49.98%)
Indiana (1936): > 43.79% (actual: 44.60%)
Minnesota (1936): > 45.32% (actual: 50.58%)
New Jersey (1936): > 39.08% (actual: 49.96%)
Ohio (1936): > 41.98% (actual: 46.72%)
Pennsylvania (1936): > 47.02% (actual: 51.06%)
Wisconsin (1936): > 46.44% (actual: 48.05%)
Wyoming (1936): > 44.48% (actual: 44.99%)

(FDR's actual 1936 vote share in Pennsylvania had been 56.88%, and in Illinois, 57.70%, about ten points in excess of what Kennedy needed to match his vote total in those states in 1960. FDR's vote total in New York in 1936, which was good for 58.85% of the state's vote that year, would have represented 45.17% of its vote in 1960. From this we can see that, while Pennsylvania and New York had slowed down in their growth dramatically by 1972, they had not yet begun to do so when those states [along with New Jersey, Ohio, and Michigan] trended heavily towards FDR in 1936 relative to 1932.)

1956

Republicans

Kentucky (1928): > 52.96% (actual: 54.30%)

1952

Republicans

Iowa (1920): > 50.02% (actual: 63.75%)
North Dakota (1920): > 59.26% (actual: 70.97%)
Tennessee (1920): > 24.63% (actual: 49.99%)
Alabama (1928): > 28.34% (actual: 35.02%)
Kansas (1928): > 57.32% (actual: 68.77%)
Kentucky (1928): > 56.19% (actual: 49.84%)
Pennsylvania (1928): > 44.87% (actual: 52.74%)
Vermont (1928): > 58.87% (actual: 71.45%)
West Virginia (1928): > 42.99% (actual: 48.08%) 

1948

Republicans

Tennessee (1920): > 39.95% (actual: 36.87%)