K Lo: The best number for Santorum in that Pennsylvania survey is 6 — the percentage of people who have a negative view of Bob Casey. That figure will do nothing but go up, up, up as we approach Election Day. As it does, Casey’s support will deteriorate — he may yet beat Santorum, but in a sense he’s at his strongest right now and will only get weaker. In order for Casey’s negatives to rise, of course, the NRSC may want to do some negative advertising. But of course not before it’s done spending hundreds of thousands of dollars on negative ads against Steve Laffey, the Rhode Island Republican who is running against Sen. Lincoln Chafee in the GOP primary. You know, because it’s so much more important to have Sen. Chafee than Sen. Santorum.