Much has been made of recent surveys that show that Tea Party members and those who are inclined to support whatever it is that they stand for are overwhelming white and disinterested in the problems of African-Americans. This does not make them racist, even if one third of them believe that Obama is not a born American (I was surprised to find that it is only 1/3 who believe this. I must be watching too much coverage of Fox news). They think that Obama works too much on the behalf of the poor and minorities. This, again, is not really racist--they are not saying that they hate African-Americans, just that they don't care about them and see any effort made on their behalf as being too much.
It is easy to conflate intolerance with self-centeredness. I am not saying that Tea Partiers are not racists, just that they may have attributes that lead them to policy preferences and political positions that do not require racism to get there.
Either way, they seek a return to a past that never existed as they face a future of increased political marginalization. The irony of opposing the census is that they might be accelerating the future--where whites in general and white right-wing folks in particular are outnumbered. An additional irony is that policies that help minorities and the poor now might really be in the Tea Partiers interests in the long run as they will need good will when they have less power in the future. One thing is certain, in the long run, they are going to need to get used to losing.