Arlen Specter's best bet is simply to join the Democratic Party. He might get re-elected that way. Certainly, the reactionary wingnut who ran against him last time would probably be crushed. In fact that might be good strategy for several Northern Republicans. Obviously, Judd Gregg would decline the honor. But there's a reason he won't run again--it's simple--he'd lose, and he knows it. Hard to see Collins of ME doing that, but it's just possible for Snow perhaps. But neither of those ladies has the slightest likelihood of being defeated whatever they do, which made it possible for them to vote their consciences, unlike all the other creepy slimy things who call themselves Republicans these days.
See, the trouble is, the Republican Party is trying to fight the Civil War all over again now. Ironic, isn't it? Since it was the founding the Republican Party that pretty much caused the War in the first place.
If we gather together all the moderate Republicans under the big tent, it would shrink the regional loonies to the South, where they would belong.
It's unfortunate those who fall by the wayside. In my own state, a great Senator, Lincoln Chafee, was defeated by a new Democrat challenger. It's comforting that the new guy--Sheldon Whitehouse--has proven to be so good. But when it comes to thoughtfulness and personal integrity, he will never come up to Linc. But Chafee chose to remain a Republican. Increasingly, that doesn't describe these people, and increasingly, that won't fly.