Obviously your under developed brain isn't going to figure it out so I'll throw you a lifeline.
Who’s kidding who? Setting the record straight on the political ancestry of modern American racism
In contrast, the Republican Party – the party of Lincoln – was, despite its own myriad racial challenges, the institution to which most Black Americans rightfully felt the greatest allegiance.
This all changed, however, during the middle decades of the 20th century. President Lyndon Johnson’s
famous/infamous lament upon signing the Civil Rights Act of 1964 that he had, in so doing, “lost the South [to Republicans] for a generation” was a seminal moment in the transition, but hardly the last. Liberal Black Republicans and conservative racist Democrats (often referred to as “Jesse-crats” in North Carolina because of their loyalty to Republican Jesse Helms) remained a part of the political scene for at least a few more decades.
setting the record staright about the historical role of Republicans and Democrats in promoting racism and white supremacy
ncnewsline.com
Those White racist left the Democratic party and sided with the republican party.
It's plain and factual history. You really aren't that bright.