To be clear, Republicans are in a much more tenuous position without Specter. But turncoats don't make their moves because they've spent too much time towing a line. They make their moves because they're conflicted. Now, it's time for the Democrats to worry, and for Specter to second-guess himself.
Byron York at the Washington Examiner says the seeds of dissent are already stewing.
Go behind the news conferences and photo-ops, and Specter's fellow Democrats aren't exactly welcoming him with open arms and warm feelings -- or even respect. Specter's defection, one well-connected party strategist told me, "seems to me like the cowardly act of a cornered man."
Underlying Democratic feelings about Specter is this fact: Even though the party faithful are happy to have Specter's vote in the coming months, they would rather have someone else come November 2010, when Pennsylvania elects its next senator.