Nate Silver notes that “vice presidential announcements often produce temporary but discernible bounces in their ticket’s polling numbers”:
Democrats should probably not worry too much if the polls move slightly toward Mr. Romney over the next week or two. For that matter, Republicans probably should not worry much if the polls fail to move toward Mr. Romney, because of the circumstances of the pick. (What if the polls actually move discernibly against Mr. Romney? Well, that might be a bad sign for him.)
Nate Cohn thinks Ryan’s home state of Wisconsin could be in play:
Although some might argue that Ryan doesn’t have the appeal necessary to give Romney 2 additional points in Wisconsin, it’s worth recalling that a recent PPP poll showed that Obama’s 6 point lead in Wisconsin fell to just 1 point if Romney decided to put Paul Ryan on the ticket. Moreover, Wisconsin is clearly willing to support controversial conservative reformist politicians like Scott Walker, so there’s no reason to presume that Ryan will be especially unpopular. And although Ryan’s statewide net-popularity rating is relatively low, that’s because a large number of undecided voters haven’t heard of him, which is hardly surprising for a congressional candidate. So there’s reason to wait and see how Ryan’s favorability numbers move in Wisconsin over the next few weeks, especially since Romney and Ryan will be campaigning in the conservative Milwaukee suburbs, where voters will probably learn to like Ryan a lot, even if they don’t know him yet.
Via The Daily Dish.