September 10, 2012 Leave a comment
Wow– to the surprise of pretty much all the professional poll watchers, Obama seems to be getting a very clear and sizeable bounce. Much more so than Romney. Obviously, I support Obama, so I’m pleased, but I was certainly of the view that there just was not enough uncertainty left among voters to lead to a bounce of the size we seem to be seeing.
Nate Cohn has a nice summary of the bounce issues:
… But no matter how you look at it, Obama looks like he has a bounce of at least 3 or 4 points, and potentially more. Rasmussen and Reuters, two trackers including a more recent window of responses than Gallup, could point to a bounce as high as six points. And Obama’s approval rating surged to 52 percent in yesterday’s Gallup approval tracker, which has a shorter three day window than the Gallup head to head poll. On balance, these factors suggest that Obama led by seven points–or even more–over the last few nights of polling, which would give Obama a bounce of about six points if it held over an entire polling sample. If any additional confirmation was necessary, PPP is trumpeting the results of their polling in Ohio, which apparently shows Obama winning by a larger margin than he did in 2008.
Of course, Obama’s bounce is hardly assured to last, since memories of the primetime speakers are fading as we speak. Historically, a candidate’s lead in post-convention polling tends to overstate their advantage, so it would be best to wait a couple weeks before concluding that Obama has opened up a decisive lead. But while it isn’t yet prudent to definitely judge the effects of the DNC, the post-convention period is one of the few instances when it’s worth scouring early returns. Analysts spend most of their time overstating the importance of campaign events, but conventions really can live up to the “game change” billing. In 2004, Bush led in just 9 of the 47 national polls conducted after July 1st and prior to the RNC. He trailed in just 7 of the 87 polls conducted after the RNC. Bill Clinton trailed before the DNC, but he never relinquished the lead afterward. It turns out that there is a decent relationship between the polls the incumbent’s share of the vote following their convention and the outcome (if someone with a better database of ancient polling is out there, it’d be interesting to see this tested on a more comprehensive data set than the Gallup poll).
And, of course, Nate Silver hits the same issue in his usual thorough manner. Now, there’s plenty of caveats, and I’m on record of saying I really want to see where the polls have settled a couple weeks after the convention, but I think to say the Obama campaign has got to be feeling really good about this right now.