My mom—to the best of my recollection—didn't have a single racist bone in her body, and if she did, she kept it very well hidden. Her parents were the same way and I never heard any of them utter anything derogatory about a person of color my entire life (although she—and her parents—had plenty to say about "the homos"…at least until I came out and educated them.
My dad on the other hand—a lifelong Democrat which proves this is not a uniquely Republican malady—always had racist undercurrents flowing through him, but it was only when he got older did it become overt with near-daily rants about "the damn Mexicans" or " the damn Blacks" taking advantage of the system and overrunning the country. I gave up trying to educate him because I knew at that point it was a hopeless battle I'd never win. His entire side of the family was like that; one of many reasons that since his death I've had nothing to do with them.