Your reasoning is a bit fuzzy. You claim that the NAACP is racist because they made a claim based on lies, but that doesn't make someone racist in any other circumstance. People are usually considered racist because they have expressed through language or iconography their belief that a race is inferior or a member of a racial group is inferior because of their membership in that racial group.

So, that's the first problem. The second problem is that tea party members have indeed performed racist acts. This has been well documented. Carrying racist signs, chanting racist slogans, and actually spitting on Black Congressmen, tend to give the impression of racist behavior. The following blog post contains specific instances of tea party racism:
http://www.1droprule.com/2010/04/man-without-country.html