Since the "Tea Party" is not an actual organisation you will always find racists and non-racists calling whatever they support a "Tea Party movement" or part of it.
I have seen videos and reports of "Tea Party" protests staged by both people that even I wouldn't consider very right-wing and by complete and utter racists and everything in between.
The typical strategy here is for the left to use racist self-proclaimed "Tea Party" supporters and point out how all of them are like that and for the right to point to non-racist "Tea Party" supporters and scream about leftie lies. The truth is that both exist and will exist until an actual Tea Party is founded with a constitution of some kind that defines what the movement actually wants.
European politics is currently undergoing the same problem: how do you create a new conservative movement without being called a racist? However, in Europe the left are more vicious. Instead of facing a loose federation of groups that use the same name but aren't organised together, Europe faces actual organisations. And the European left still calls them racists, simply because OTHER organisations, which have NOTHING to do with the new conservative groups are racist.
So, yes, it's true. The Tea Party movement is racist. It's also not racist. It depends on the views of whoever calls himself a representative of the movement at any given day. Sarah Palin is absolutely not a racist. But the Paulians have definite connections to white supremacists and other "Tea Party" are even worse.
This is the problem. When a conservative Republican sees the Tea Party movement, he sees normal Americans, black and white, with family values standing against big government because of the bad things big government does.
But when liberal Democrats see the movement, they see WHITE Americans with reactionary values standing against necessary government because of the good things government does. And that's if they see the same people as the Republican just did. It gets worse when the libdem sees the racists who also flock to the Tea Party movement and see them as representative of the movement.
The solution is the same in both the European and the American case: preserve the movement, drop the racists even if they agree with the principles of the movement, and get representatives from minority groups!