Of course--he's about 846 years old and not in such great health.
Whatever advantages he gives the dems, I'm kinda failing to see them. Not that I'd kick him back across the aisle or anything; I'm just sayin': the guy looks like he needs to add "of death" after his last name.
So why'd he switch? It could be that he just wanted to distance himself from the party of Satan. Or perhaps he just wanted to get a rise out of Sammy Bareback, who's shocked, just shocked! that Arlen could do such a thing.
So why? He's obviously not that proud of this decision, or he'd have updated his web site, which as of this writing, was still blaring this hedline:
Specter Proposes Innovative Agency to Accelerate Cures for Diseases