More important than the political calculation of Specter's defection is the fact that Specter really is a moderate Republican. He is not really a Democrat. This is the man who gave us Justice Thomas, after all.
At the Obama Town Hall Meeting in Harrisburg on Sunday night, capital city bloggers (Progressives, all) were gloomy. Looking around the place, they could find nobody from state or city government, not even "down to the third degree," as one put it.