I personally think that most people are at least a tiny bit racist. What I mean is, a lot of children are raised to "look after their own", even if its not on a major level. You can ask pretty much anyone who says, "I'm not racist!" the following question:
"Could you see yourself personally marrying someone of [insert race here] descent?"
My suspicion is that a higher percentage of answers would probably be "no", and when you get past the ones who use defensive excuses, I think it'll likely boil down to race, at least to some degree, and its not always "I hate this or that race".
As for myself, I'm fairly sure I'd have problems marrying an African woman, yet some of my friends are African. At the same time, I'd at least consider marrying a Spanish or Latin woman. I think if quite a few people were totally honest with themselves, they'd find themselves in a similar situation.
I hope no one was offended by this post, and if they were, I sincerely apologize.