After the American Civil War, Southern states gained seats in the House of Representatives and representation in the Electoral College since blacks were fully counted for election purposes, instead of being counted as only three-fifths of a person. Resentment stemming from the Civil War and the Republican Party’s policy of Reconstruction kept Southern whites in the Democratic Party, but the Republicans could still compete in the Southern States with a coalition of blacks and highland whites. After the North agreed to withdraw federal troops under the Compromise of 1877, and the further failure of the "Force Bill" (to protect black voting) in 1890, Southern blacks, the base of Republicans' power in that region, became increasingly disenfranchised. The white Democratic Party in the South enacted Jim Crow Laws and, through the terror of vigilantes and the Ku Klux Klan, undertook other measures to ensure and enforce black disenfranchisement. As blacks lost their vote, the Republican Party lost its ability to effectively compete.
The South became solidly Democratic until the middle of the 20th century. During this period, Republicans held only a few House seats from the South. Between 1880 and 1904, Republican presidential candidates in the South received between 35 and 40 percent of that section's vote (except in 1892, when the 16 percent for the Populists knocked Republicans down to 25 percent). From 1904 to 1948, Republicans broke 30 percent of the section only in the 1920 (35.2 percent, carrying Tennessee) and 1928 elections (47.7 percent, carrying five states). The only important political role of the South in presidential elections came in the 1912 election, when it provided the delegates to select Taft over Theodore Roosevelt in that year's Republican convention.
During this period, Republicans occasionally supported anti-lynching bills, which were filibustered in the Senate, and appointed a few black placeholders, but largely ignored the South. It was not until the 1928 election that the situation changed. In that year, Republican candidate Herbert Hoover rode the issues of prohibition and anti-Catholicism to carry five former Confederate states, with 62 of the 126 electoral votes of the section. After his victory, Hoover attempted to build up the Republican Party of the South, transferring patronage away from blacks and toward the same kind of white Protestant businessmen who made up the core of the Northern Republican Party. However, with the onset of the Great Depression, which severely impacted the South, Hoover soon became extremely unpopular, and the gains of the Republican Party in the South were lost. In the 1932 election, Hoover received only 18.1 percent of the Southern vote for re-election. The subsequent policies of Franklin Roosevelt were very popular in the South, precluding Republican growth in the region.
In the 1948 election, after Truman had desegregated the Army, a group of Southern Democrats known as Dixiecrats split from the Democratic Party in reaction to the inclusion of a strong civil rights plank in the party's platform, following a floor fight lead by Minneapolis Mayor (and soon-to-be Senator) Hubert Humphrey. They formed the States' Rights Democratic, or Dixiecrat, Party, and nominated Governor Strom Thurmond of South Carolina for president; he won four Southern states. The main plank of the States' Rights Democratic Party was maintaining segregation and Jim Crow in the South. The Dixiecrats, failing to deny the Democrats the presidency in 1948, soon dissolved, but the split lingered. (In 1964, Thurmond was one of the first conservative southern Democrats to switch to the Republicans).
