We’ve long thought that even in blue Massachusetts, defeating Scott Brown would be a formidable task for any Democrat. Brown’s a Republican, sure, but he’s demonstrated a mavericky, independent streak that’s popular with voters, and even though the tea party was integral in his upset victory in January 2010, Brown doesn’t act like a typical tea-party legislator — by which we mean a loud, angry hysteric. Not to mention: that truck, that face, those sweaters! And yet: For the first time, at this very early date in the 2012 election season, Brown is trailing in a poll. His just-announced challenger, Harvard professor and consumer advocate Elizabeth Warren, is barely edging Brown by two points, according to PPP. Watch for Brown to take more moderate positions in the coming months, and possibly remove his shirt for no apparent reason.