When is a Teabagging Republican not a Teabagging Republican? When he's running for re-election in politically-moderate Massachusetts and knows he can't pander to a miniscule but rabidly-vocal segment of the voting population and hope to get re-elected....
Newly-elected Senator Scott Brown, perhaps better known as the tucked Playgirl model candidate (eh, moderately NSFW), won Ted Kennedy's senate seat thanks in large part to the Dems fielding a weak candidate unworthy of filling such large shoes, but also in part thanks to support from the Teabaggers. And true to form, they saw his victory as a victory of their own, and a portent of things to come.
So, when the Teabaggers, fronted by Teabagging Luminary/Visionary Sarah Palin, decided to hold a "massive rally" in Boston, invited Mr. Brown to attend, he said, um, thanks but no thanks. At a time when the IRS proves more popular than the Teabaggers, even Teabagger-supported politicians know their support is toxic to the majority of correct-thinking voters.
Expect more of the same as GOP politicians jettison the brain-dead, thuggish political neophytes they shamelessly fostered and supported while it was expedient.