party affiliation to the GOP...happened after the Democratic Party fought for...and won...the Civil Rights Act...they couldn't stand it and the Republicans welcomed them...you can read all about it...if you have any desire to understand and know the truth...there are scores of articles, papers and books on this topic...to not know about this is truly "Willful Ignorance".
btw, IMO this example of you not understanding this historical fact is another reason why schools need to teach the truth about the country's racial history...we can't make progress if citizens are ignorant of the facts.