[officemonkey]

It _started_ even earlier. In 1948, Strom Thurmond ran for President as a Dixiecrat (Democrat for Racial Segregation), which is one reason why Truman v. Dewey was so close.

In 1952, Robert Taft wanted to run for President using the "southern strategy" to woo disaffected Democratic voters, but Eisenhower decided to run, and that put an end to that strategy until Nixon was more successful in 1968.

Basically, the south became squishy on Democratic Party once northern Democratic Mayors (and FDR) realized that African-Americans were a strong labor voice and a powerful voting block. "The Party of Lincoln" (GOP) had been ignoring African-Americans since TR was in the White House.