Third party second-place showings at the county level

The last time anyone other than a Republican or Democrat carried a county was 1992, when Ross Perot carried a scattering of small counties across the country. (The largest was Grayson County, Texas, which cast 38,332 votes, followed by Somerset County, Maine, which cast 26,424 votes. The smallest was Loving County, Texas, which cast 96 votes.) Before that, the last time anyone other than a Republican or Democrat carried a county was 1968, when George Wallace carried a large number of counties in the South. 

The seven straight elections from 1996 through 2020 is already a historically long run of consecutive elections without anyone other than the Republican or Democrat carrying a county. There were only five consecutive elections between Wallace carrying counties in 1968 and Perot carrying counties in 1992. Before that, unpledged electors carried some counties in 1960; T. Coleman Andrews carried at least two counties in 1956 (one in Virginia and one in Tennessee); Strom Thurmond carried counties in 1948; the 'Texas Regulars' carried a county in Texas in 1944; Robert La Follette carried counties in 1924; Eugene Debs carried four counties in 1912 (aside from everything else going on in that election); James Weaver carried counties in 1892; Alson Streeter carried at least two counties in 1888 (one in Michigan and one in Texas); James Weaver (running as the Greenback nominee) carried some counties in Missouri, Texas, Arkansas, and Mississippi in 1880; John Hale carried counties in Ohio and Wisconsin in 1852; van Buren carried counties in 1848; and William Wirt carried counties in 1832. (And, obviously, nothing need be said about 1856 and 1860, although there is a certain sense in which all the important nominees in those elections could be considered 'major-party nominees'.)

That is not necessarily a comprehensive accounting of occasions on which non-major-party candidates carried at least one county in a presidential election, but it is enough to show that, before the run of five elections from 1972 through 1988, the most consecutive elections in which no-one other than the two major parties carried a county was four (possibly 1864-1876, 1896-1908, and 1928-1940). So 1992 was itself in some ways only an interruption of a trend that seems to have already begun after George Wallace (especially considering how few counties Perot carried relative to his national strength). In the interim, John Anderson had become the first non-major candidate to get over 5% of the national vote without carrying a single county. Perot himself would become the second in 1996.

Not only that, but Anderson did not come in second in any county in 1980. Perot did come in second in two tiny counties in 1996: Arthur, NE (which cast 258 votes), and Loving, TX (which cast 77 votes). 

1992 was itself the first time since 1972 that anyone other than the Republican or Democrat came in any better than third in a county; in 1972, Schmitz came in second in Jefferson, Lemhi, Fremont, and Madison Counties, Idaho (which cast from 2,923 to 5,216 votes). 

There has now been an occasion of a non-major candidate coming in second in a county since 1996: in 2016, Evan McMullin came in second in 15 counties in Utah and several counties in Idaho. Two of these (Utah County, Utah and Davis County, Utah) cast more than 100,000 votes. Utah County, the larger of the two, cast 201,551 votes.

Some fairly impressive second-place county finishes in the past by minor candidates who were not doing all that well in the national vote were:

Herman Preston Faris (Prohibition), 1924, in Dade, FL (29.95%)

Eugene Debs (Socialist), 1920, in Lake (31.29%), Isanti (20.18%), and Roseau (18.75%) Counties, MN; and Milwaukee (30.16%), Manitowoc (22.95%), Sheboygan (19.64%), and Marathon (21.40%) Counties, WI

Parley Christensen (Farmer-Labor), 1920, came in second in many counties in South Dakota (including the state's second- and third-largest at the time, Brown [29.31%] and Beadle [24.58%]); and lost Hutchinson (41.73%) and Roberts (40.23%) Counties, SD to Harding by less than 10%. He also came in second in a number of counties in Washington State, including King County (24.99%).

Allan Benson (Socialist), 1916, in Dewey (32.87%), Seminole (28.33%), Beckham (27.15%), Stephens (26.61%), and Marshall (25.50%) Counties, OK (in all of which he got over 25% of the vote)

Eugene Debs (Socialist), 1908, in Lake (31.75%) and Clearwater (15.69%) Counties, MN

Thomas Watson (Populist), 1904, in Clay County, KS (12.50%), Custer County, NE (23.73%), and Hand County, SD (17.04%)

Silas Swallow (Prohibition), 1904, in Venango County, PA (20.48%)

I've been limiting myself to counties that are (somewhat subjectively) reasonably-sized, and in which the minor candidate in question got a reasonable percentage of the vote. However, in the interest of simply documenting the existence of a county in which a minor candidate came in second, John Woolley (the Prohibition nominee) came in second in Dooly County, Georgia in 1900 (and Wharton Barker, the Populist nominee, came in second in Franklin and Upson Counties, Georgia in 1900). In 1896, John Palmer, the Gold Democrat, came in second in Bibb County, Georgia. 

I can't tell about the period from 1864-76, but it seems as though the period from 1928-40 might itself have already been somewhat unusual in that--although I haven't been able to confirm this--it seems that only in 1936, out of those four elections, did any minor candidate even come in second in any county. (In 1936, Lemke came in second in some counties in North Dakota.) If that's true, 1928 would have been the first election in decades in which no minor candidate had come in second in any county, and 1932 would have been the second.

Actually, this is not true: in 1932, William Foster--the Communist nominee--came in second in Elmore County, Alabama. Now, if there was a region of the country where minor-party second-place finishes seemed likely without necessarily being that significant, it was the Deep South, given that, at this time, Republicans regularly got less than 5% in many Deep South counties. In Elmore County, Hoover did get 4.37%, but Foster--the Communist--got 7.56%, in a county that cast 3,638 votes. (In a case that is more exemplary of what I was talking about, Norman Thomas also came in second in Greene County, Alabama in 1932, with 2.88% and 20 raw votes. Or, even more so, William Upshaw [Prohibition] came in second in Baker County, GA with 0.46% and three votes [Hoover got two].) It still seems likely that 1928 was the first election in decades in which no minor candidate came in second in any county, although I haven't access to county-level data for the two Deep South states that were Smith's best states and were consistently the most lopsidedly Democratic states in the country (South Carolina and Mississippi).

It might not be coincidental that Smith was stronger in the North (compared to how he was running nationally) than previous Democratic candidates, and Hoover, stronger in the South than previous Republican candidates. In the wake of the New Deal, Democrats gained permanent constituencies in areas of the country that had simply been ancestrally Republican before. In 1920, Harding swept every county in 22 (probably 23) states (see here for a discussion on Manistee County, Michigan in the 1920 election). Even McGovern in 1972 was shut out at the county level in 'only' 19 states. Conversely, with the advent of civil rights (as well as when they nominated the first Catholic major-party nominee), Democrats lost their Soviet-like grip on the Deep South. In 1932, Franklin Roosevelt swept twelve states' counties (in 1936, he would exchange sweeps of Alabama's, Arkansas', Louisiana's, Oklahoma's, and Texas' counties, for sweeps of Delaware's, Montana's, California's, and Oregon's, to sweep eleven states' counties). In 1964, Goldwater was shut out of 'only' nine (probably ten) states' counties. Furthermore, of the four states with eight or fewer counties (Connecticut, Delaware, Hawaii, and Rhode Island), all four were amongst both the ten states whose counties Lyndon Johnson swept and the 19 states whose counties Nixon swept in 1972. None of them was amongst the 12 states whose counties FDR swept in 1932 (one, Delaware, was amongst the 11 whose counties he swept in 1936).

As an example of this, Lake County, MN--a county in which the Socialist nominee Eugene Debs came in a strong second at least twice--never voted Democratic from its first participating election in 1868 through 1912 (in 1912, it was one of the four counties that actually voted for Debs). It gave Wilson a 38.13% plurality in 1916 (Benson took 26.50%), but then voted Republican in 1920, for La Follette in 1924, Republican in 1928, and Republican in 1932--before going on to vote Democratic in every election from 1936 on, to date.

Still, this doesn't seem enough to explain why things like Eugene Debs getting 30.2% of the vote in Milwaukee County in 1920, or Parley Christensen getting 24.99% of the vote in King County, WA in 1920 (when it was already casting a bit over 100,000 votes), doesn't happen anymore. Polarisation might explain this, but polarisation should also make it easier for minor candidates to come in second in very polarised counties (especially if they are small). This is, after all, what allowed for some relatively trivial second-place county finishes in the Deep South before the 1940s. Gary Johnson came relatively close to a relatively trivial second-place finish in tiny Harding County, SD in 2016, where he got 4.03% and Hillary Clinton got 4.94% (and which cast just 769 votes overall). Obviously, this county is practically void of Democratic support, and Johnson coming in second wouldn't even have been all that impressive (it would not have required him to do as well as a Communist did--in a larger county--in 1932); and yet he fell short. Similarly, in Loving County, Texas, which cast 65 votes in 2016, Hillary Clinton got four votes (or 6.15%). It doesn't seem that it should have been hard for the Libertarian nominee to beat that, but Gary Johnson got only one vote (behind, in fact, Jill Stein, who got two). On the other side, if we are counting Kalawao County, Hawaii (which I haven't been), then someone other than Evan McMullin did come in second in a county in 2016--Jill Stein got five votes (or 25%) to Trump's one vote (or 5%) that year. But in 2020, Trump managed to come in second place in the county, despite that the number of votes he got remained unchanged--one.

Democrats don't get quite as unanimous support in their large urban counties, and in general, one expects large counties to behave less anomalously in any case. DC's wards are not treated as county-equivalents, but even if we get into DC's individual wards, Trump came in second in every ward in 2016, despite getting 1.64% in Wards 7 and 8 (and no more than 8% in any of DC's wards). The only large urban counties I could find in which Trump got less than 10% of the vote in 2016 were San Francisco (9.3%), The Bronx (9.5%), and Manhattan (9.7%). He came in second in all of them, which is not that surprising at those percentages (although he was getting well below Debs' 1920 vote share in Milwaukee County in all of them). Trump also got less than 10% (i.e., 8.32%) in Shannon County, SD, where one might expect Jill Stein to have done well enough to come in second in those circumstances (she got 10.39% in Sioux County, ND)--but Trump came in second in Shannon.

From 1972 on, the major-county nominees who have come in less than second in at least one county have been: McGovern in 1972; both George H. W. Bush and Bill Clinton in 1992; Bill Clinton in 1996; and Hillary Clinton in 2016. (The reason I'm not counting Kalawao County is not simply [or even partly] its tiny size.) Before 1972, I couldn't say comprehensively, although Eisenhower came in third in Fayette County, TN and Powhatan County, VA (and in some counties in Mississippi, behind unpledged electors) in his 1956 landslide; it was Coolidge in 1924 who came in third in Dade County, FL (which was already casting over 10,000 votes); and Harding came in third in Calhoun County, FL in 1920 (behind Cox and the Prohibition nominee); so it wasn't unusual for national winners--even Republican national winners--to come in lower than second in a county before Bill Clinton.