a little history
blacks were mostly Republicans from the Civil War to the 1930s...they turned against Hoover and the Republicans because of ineffectiveness dealing with the Depression...but they didn't become overwhelmingly Democratic until 1964 (LBJ vs Goldwater)...LBJ famously said that "we have lost the South for a generation" after he signed the 1964 Civil Rights Act...and they have indeed lost the South...actually for more than one generation...I think black voters are open to voting for either party...the thing that has kept them loyal Democrats is the Southern Strategy pursued by the GOP...this Southern Strategy is a fusion of ideas that appeal to cultural conservatism and white racial grievance...the cultural conservatism is actually a potential selling point to many black voters...but they refuse to overlook the second part and I can't say I blame them