I've been quizzing political folks today about the Pennsylvania races. Just got off the phone with a top Pennsylvania Republican to get his thoughts on Specter-Sestak and the PA-12 race (John Murtha's seat). Upshot: both races have razor-thin margins right now--and they're intricately connected. My GOP source says the latest internal poll has Tim Burns deadlocked with Mark Critz at 45 percent, which is exactly where they've been stuck for awhile. Independents have begun to break, but they're breaking evenly between the candidates.
As a result PA-12 could be--I'd guess, will be--decided by who turns out for the Democratic Senate primary, since all polls are based on a "filter"--a guess of what the electorate will look like. If Democrats turn out in heavier numbers than anticipated, Critz should prevail (it's a majority Democrat district). But there's a countervailing force to consider. While Democrats have a sexier primary match up (not much interesting on the GOP side), the intensity is higher among conservatives. So even the intangibles are offsetting.
For what it's worth, my GOP source doesn't think Specter is going to pull it off: "That ad they're running against him--'Why did you switch parties? To win an election'--is just killing him, especially out west. And the way he says it is so smarmy."