So who? Romney? I'd have to say that seems like the most likely scenario at the moment. But only because the other scenarios don't seem possible.Slick Dancin' Mitt himself. Because he's the least ridiculous candidate. The post itself makes the great point that basically any Dem would vote for Clinton (mostly), Obama (definitely), or Edwards (almost surely), but the Republican slate is mixed.
Time for a 3d party right wing candidate. I say draft Pat Buchanan.