Please don't speak for other people when you have no idea what you are talking about.
At least for me - I view Clarence Thomas and Michael Steele as "token black guys" for the Republican party intended to mask the appearance of racism. Steele is an idiot, but he's the head of the RNC because the Republicans need to be able to point to something and say "Look, a black guy, see we are not racist".
And sure not all Republicans are racist, probably only a minority percentage are. But that does not change facts like this: In the last 100 years there have been exactly three Republican black men elected to the House of Representatives (Oscar Stanton De Priest, Gary Franks, and J. C. Watts). This is hardly representative of the general populous.
So in any case, if your attacks against Obama are not logical, I tend to suspect racism, as racism is not logical. And yes, I suspect many people are subconsciously racist so that even they are not aware of it.