Well, I think it depends on what you mean by racist...
If you mean that they believe on is superior over another, blah blah blah... or just that they fixate on race as an aspect of every day life.
If its the first, then there are plenty of rich white folks that don't dwell on race much at all, but nevertheless are what you mean by racist... that they do think that other races just can't quite cut it, though they often don't know why.
If its the second, then the answer is hands down lower middle class blacks.
And if its in terms of in the media, it is unquestionably blacks since they're the only ones who are allowed to even acknowledge the existence of races since whites would just be magically labeled instantaneously as racist.
So black producers are allowed to produce whatever cheap, racist pieces of crap movies where all the white men are uptight, Mayonaise-eating, castrated automotons, and white women are stupid innocent airheads with a sex kitten locked up inside just waiting for Mandingo to come along... and by the end of the flick they've come to the realization that they can't be black, but at least they can try...