One thing to keep in mind is that there is no central organization to the "Tea Party". It's still all pretty grass roots activisim, or at least very local in nature. There's several .orgs that have a national presence now and act as quasi clearing houses, but they don't speak for anyone.
So if one local Tea Party group wants to do something as boneheaded as protest a mosque, it does not really mean anything about any other Tea Party groups in other states, or even in other nearby cities. (And as noted, they reconsidered too...)
Judging by how recent polls say 70% +/- of self-described Tea Party "members" don't want to see any Medicare cuts, it seems to me that being "Tea Party" does not even mean what the Right thinks it means either, much less the Left's knee-jerk racism mantra.