Jay Cost of RealClearPolitics pointed me to University of Chicago political scientist Boris Schor’s analysis of Scott Brown’s voting record. According to a metric he devised with Princeton’s Nolan McCarty, Brown is on the left end of the Republican caucus in the Massachusetts State Senate, and Massachusetts liberals as a whole tend to be well to the left of Republicans in the country as a whole.

Brown’s score puts him at the 34th percentile of his party in Massachusetts over the 1995-2006 time period. In other words, two thirds of other Massachusetts Republican state legislators were more conservative than he was. This is evidence for my claim that he’s a liberal even in his own party. What’s remarkable about this is the fact that Massachusetts Republicans are the most, or nearly the most, liberal Republicans in the entire country!

So why has Brown attracted such a devoted following from grassroots conservatives around the country? One obvious reason is that many hope that if Brown is elected to the U.S. Senate, he will block the Democratic health reform effort. Yet the enthusiasm might also reflect political realism.

In other words, what began as a puzzle turns out not to be much of oneat all. It makes perfect sense that Scott Brown, a liberal Massachusetts Republican, has attracted Republican and conservative support. He’s perfectly suited for his liberal state electorate. Dede Scozzafava, in fact considerably more conservative than Scott Brown was not nearly so well matched to her intended constituency, the relatively conservative 23rd District that had returned moderate conservative John McHugh since the 1992 election.
What this shows, however, is that the conservative base in the United States, far from dragging their party moblike into an unelectable extreme, has made the decentralized decision to support the realistically best candidate they can relative to the context in which he’s being elected. The 23rd special district election can also be seen in this light; throwing Scozzafava overboard made far more sense in the context of that electorate.

This, of course, runs against the Frank Rich “purgist” narrative that has proven so attractive to critics of the right.

At the same time, Brown is emphasizing his conservative credentials, as you might expect given the climate. In a Boston Globe op-ed, he offered a perhaps overly simple economic plan.

My plan for the economy is simple: an across-the-board tax cut — in the tradition of John F. Kennedy — for families and businesses that will increase investment and lead to immediate new job growth. More tax increases will hurt our recovery. That’s why I have taken a no-new-tax pledge. My opponent will raise taxes.

Given that Brown doesn’t also outline how he intends to shrink our spending obligations, I have a hard time taking this seriously. That said, one gets the impression that he is an impressive public servant and that his Democratic opponent’s accusations are unsound to say the least.