Unlike Gov. Ed Rendell, I doubt very much that yesterday's rain in Philadelphia sent Arlen Specter to his defeat in the Democratic primary. And unlike a lot of other people, I'm not so sure that generalized anti-incumbent sentiment was all that big a factor either. I think that after 30 years of watching Arlen Specter put political advantage over principle at seemingly every turn, Pennsylvania voters were simply tired of the guy.
It doesn't have to have a bigger meaning than that.