Will Trump keep the Rushmore State red?

This is an update of a post written prior to the 2016 election. Unofficial election results indicate Trump/Pence carried South Dakota with 61.77% of the vote, slightly exceeding the 61.53% the ticket won in 2016 and notching the third-best showing all-time for a GOP presidential ticket in SD.

The 2020 presidential election is the 33rd since South Dakota became a state in 1889.  In that time, South Dakota has cast its electors for the Republican nominee for president 29 times.  In only four elections has South Dakota supported the Democratic nominee, including one instance in 1896 when the Democrats and Populists ran a joint or “fusion” ticket.

Could 2020 be the fifth time that a Democrat carries South Dakota?

It seems unlikely.

Trump and Biden

According to the KELOLAND/Mason-Dixon poll, the Republican ticket of Donald Trump and Mike Pence leads Democrats Joe Biden and Kamala Harris by a margin of 51% to 40%. Four years ago, the poll projected a Trump win 44-37; he in fact won the state by a much larger margin, defeating Democrat Hillary Clinton 62-32.

FiveThirtyEight, the renowned statistical forecasting site, gives Mr. Trump a 94% chance of carrying South Dakota, and predicts a result of Trump 57.0%, Biden 41.6%.  (The FiveThirtyEight predictions are as of 9:30 PM on October 27; they fluctuate often.)

In 2016, Trump and Pence made the third-best showing by a Republican presidential ticket in South Dakota history; only the Eisenhower/Nixon ticket in 1952 and the Reagan/Bush reelection ticket in 1984 won a greater share of the state’s votes. To put the South Dakota contest in context, here is a list of each presidential election in South Dakota, ranked by the total share of the vote won by the Republican ticket:

(see notes regarding this chart at the end of the post)

On average, a winning Republican ticket in South Dakota has won 55.7% of the vote, and prevailed over the nearest opponent by 15.9%.  If the FiveThirtyEight prediction is correct, Trump/Pence will be just above the average vote share with 57%, but just below the average margin with 15.4%.

South Dakota has supported the Democratic nominee in four elections, each more than half a century ago:

  • In 1896, South Dakota narrowly supported Democrats William Jennings Bryan of Nebraska and Arthur Sewell of Maine.  Bryan was also the nominee of the Populist Party, and it was this nomination that carried him to victory in South Dakota.  That same year, South Dakota elected its only Populist governor, Andrew E. Lee and several other Populist officials.  The Bryan/Sewell ticket was defeated nationally by Republican Governor William McKinley of Ohio and Garret A. Hobart of New Jersey.
  • In both 1932 and 1936, South Dakota supported the Democratic ticket of Franklin Delano Roosevelt of New York and John Nance Garner of Texas.  The depths of the Great Depression hit South Dakota particularly hard, as the state was already suffering from a farm crisis that was exacerbated by plummeting crop values after the stock market crash, as well as record-setting droughts and a grasshopper infestation.  The Roosevelt/Garner ticket defeated President Hoover and Vice President Curtis in 1932, and then rode the success of the New Deal program to a massive reelection victory in 1936 over Kansas Governor Alfred M. Landon and newspaper publisher Frank Knox – the Landon/Knox ticket carried only Maine and Vermont. South Dakota abandoned FDR when he sought a third term; the state supported challengers Wendell Willkie in 1940 and Thomas E. Dewey in 1944.
  • Finally, in 1964, South Dakota supported the Democratic ticket of President Lyndon B. Johnson of Texas and U.S. Senator Hubert H. Humphrey of Minnesota.  Johnson had become president nearly a year earlier after the assassination of President John F. Kennedy.  He won a landslide victory over the conservative Republican Senator Barry Goldwater of Arizona, whom Johnson successfully portrayed as being too extreme to be elected.  South Dakota also certainly was swayed to support Johnson’s running mate, Senator Humphrey, who although representing Minnesota was a native of Doland, South Dakota and whose family operated Humphrey Drug in Huron, South Dakota.

Notes on the chart:

  • Third party tickets are only listed if they received at least 5% of the vote in South Dakota.  For that reason, many of the results listed do not total to 100%.
  • In 1912, the national election was a three-way contest between Republican incumbent William Howard Taft, former President Theodore Roosevelt running as a Progressive, and Democratic Governor Woodrow Wilson of New Jersey.  In South Dakota, however, the Republican Party was controlled by pro-Roosevelt forces, who contrived to have the Progressive Roosevelt ticket nominated as the state’s official Republican ticket, therefore depriving Taft of a place on the ballot.  
  • In 1924, the Progressive LaFollette/Wheeler ticket finished ahead of the Democratic ticket of Davis/Bryan, and it is the Republican ticket’s margin over LaFollette that is reflected on the chart.  LaFollette only carried his home state of Wisconsin but ran strong in other midwestern states.
  • All South Dakota presidential election results are taken from Dave Leip’s Atlas of U.S. Presidential Elections.