News Report: Arlen Specter Loses Senate Seniority
There is a reason, in 2001, when Jim Jeffords left the Republican Party he became an independent instead of a Democrat. It's the same reason Joe Lieberman stayed in his own party-of-one instead of appending a big red R to the end of his name even while campaigning for Republicans in 2008. They may have spat on the bridge, they may even have smeared stale feces on the bridge, but they didn't burn the bridge behind them.
The reason Jeffords and Lieberman didn't go full monty and switch parties is that the only power they had was their disloyalty. They kept the ability to switch back if they had to. Even though Democrats like me wanted Lieberman drawn and quartered and have his head stuck on a pike in the Capitol Rotunda, he had kept enough vagueness to his loyalty that he could play the lost sheep returning to the fold and get away with it. Specter didn't do the subtle shift, he swapped teams. Then Specter wasted no time announcing his intention to stab his new allies in the back every chance he got.
He's stuck. Specter is a Democrat now whether he likes it or not. The Republicans won't take him back. There can be no "it was a mistake and all is forgiven" charade. So Specter gets what Lieberman avoided - the very last seat in the very last row of the Democratic caucus.
No one trusts a quisling. No one likes a quisling. And no one is going to give up their senority on the Appropriations Committee to a quisling.
You Can't Go Home Again is also a good book.