The researchers found identification with the tea party was associated with anti-black prejudice, libertarian ideology, social conservatism, and belief the nation was in decline.

you don't necessarily have to be racist to join the Tea Party, but once you do your racism will grow over time. I imagine it was much the same for young members of the Klu Klux Klan. "You know I used to only KIND of dislike the n***ers, but after burning down a few of their churches and hanging them from trees I find that I hate them more than ever!"