It looks like Sestak is really moving in the race against Specter. Good for him. I was impressed with him during the town hall debates on the health care bill, and Sestak has the resume and the rhetorical chops to be a very good US Senator.
Specter's biggest appeal all along is that he would give the Dems another seat (and that he would beat Toomey in the general election). More and more, however, voters aren't really buying it.
Ironically, Obama's election in 2008 (running on the case, essentially, that competence matters more than party) would short circuit Specter's main appeal to voters in this state.