Many people will say that it's about time Sen. Arlen Specter of PA changed parties and became a Democrat. Certainly conservatives (or self-styled conservatives) who want the Republican Party to be their domain are likely pleased. I'm not so sure. Specter's defection gives the Democrats something close to a filibuster-proof majority depending on the issue, and I would just as soon Obama not have that. And although Specter has always been a liberal by "big-tent" Republican standards, he has also done yeoman work for the Republicans from time to time, as during nthe Clarence Thomas confirmation hearings.
Arlen Specter visited the Register editorial board some years ago (probably 1999) when he undertook a brief run at the presidency. I found him pleasant and thoughtful and more than willing to discuss his several differences with our philosophy in a sustained and civil manner. I have no particular interest in the future of the Republican Party, not being such a party animal myself. But I think the party is weaker (and probably more clueless) for Specter being gone.