While I stand by my claim that the significance of Arlen Specter’s party switch has been exaggerated, it’s still interesting to see how his voting patterns have changed since he defected from the GOP caucus.

Stanford’s Simon Jackman has estimated an ideal point model for the 111th Senate treating Specter as a new legislator since the switch. Though Specter’s verbal statements about “card check,” health care reform, and the Minnesota Senate race have provoked a backlash among his new party, his roll call votes so far actually place him to the left of twelve Senate Dems (though, as Jackman emphasizes, there is still a great deal of uncertainty in the estimate):

Given the prospect of a competitive Democratic primary in 2010, I’d guess Specter will continue to move left. The fact that he is an unprincipled hack should help facilitate this process.