One thing was abundantly clear from our Pennsylvania poll this week- Democrats are very, very lucky that Arlen Specter lost their party's nomination for the Senate.
Specter had pretty bad approval ratings in late March when we last polled the race, with 34% of voters approving of the job he was doing then to 52% disapproving. But now those numbers are even worse, with Specter's approval dropping all the way down to 30% and his disapproval creeping up to 55%. It's not impossible for any politician to win a race with approval numbers that bad- I still think Pat Quinn could get reelected in Illinois- but I do think it's impossible for a politician in a state as evenly divided as Pennsylvania to win with those kinds of numbers.
Part of Specter's decline predictably can be tied to falling fortunes with Democratic voters in the wake of his primary loss. He's gone from a 53/30 approval spread to a 46/33 one with them. But he's seen an even more dramatic drop with independents. He was at 32/52 with them three months ago and that's now tanked all the way to 19/67.
If Specter had pulled out the primary it's a pretty safe bet we'd be six months away from Senator Toomey. With Sestak as the nominee Democrats are at least even money to hold the seat, and if I had to put money down on it today I'd guess Sestak ends up winning in November when Democrats get a little more tuned into the race.