1964 United States presidential election in South Dakota

The 1964 United States presidential election in South Dakota took place on November 3, 1964, as part of the 1964 United States presidential election. Voters chose four representatives, or electors, to the Electoral College, who voted for president and vice president.

South Dakota was won by incumbent President Lyndon B. Johnson (D–Texas), with 55.61 percent of the popular vote, against Senator Barry Goldwater (R–Arizona), with 44.39% of the popular vote. As of 2024, this is the only presidential race since 1936 where South Dakota voted Democratic (although it nearly did so in 1976 for Jimmy Carter), as well as the last time a Democrat won any of the following counties: Pennington, Lincoln, Meade, Yankton, Custer, Bennett, Clark, Hamlin, Hand, Hyde, Jackson, Jones, Lyman, Mellette, Potter, Stanley, Tripp, and Walworth. This is also the last time that South Dakota voted more Republican than North Dakota, and the last of only 5 times since statehood that South Dakota voted against the Republican presidential nominee.