Brown being hardcore Conservative and/or TeaParty was a dis-information campaign put out by Rats. How anyone could of lived thru the primaries, not to mention his voting record and platform and thought he was anything other than a middle of the road RINO is unfathomable.
But in a State where the legislature is 85% Dem and as the only Republican member of the Congregational delegation. Even with all the backlash not one Dem lost a Congressional bid in Mass. And people want to spend money here to unseat Brown.
As for probable Dem Challengers. Mike Capuano has voted with his Dem colleages 98.1% of the time. And is listed as more liberal than 90% of Congress. (as compared to Brown’s reported voting with Rep’s 81% according to the Washington Post)
I doubt he votes 81% with CONSERVATIVES.