Nate Silver: Sept. 8: Conventions May Put Obama in Front-Runner’s Position
A new blog post from him, echoing what he said in a tweet earlier:
http://fivethirtyeight.blogs.nytimes.com/2012/09/08/sept-8-conventions-may-put-obama-in-front-runners-position/
What's most interesting here is what he has to say about how far ahead he believes the polls are showing President Obama since Clinton's speech on Wednesday, which Silver considers "the pivotal moment of the convention":
Over all, that means that only about 30 percent of the data from the Gallup poll post-dated Mr. Clintons remarks.
If you do the math, it implies that Mr. Obama must have been leading Mr. Romney by 10 or 11 points in the minority of the poll conducted since Mr. Clintons speech for him to have gained three points in the survey over all.
In the table below, Ive run through the same calculation for the other tracking polls. The results imply that Mr. Obama has run about nine points ahead of Mr. Romney in the portion of the Ipsos poll conducted since Mr. Clintons speech, about eight points ahead in the RAND poll, and about four points ahead in the Rasmussen poll.
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On average between the four polls, it appears that Mr. Obama must have held about an eight-point lead since Mr. Clintons speech in order to have gained so much ground so quickly.
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But on Friday, I wrote that Mr. Obama might eventually hold about a five-point lead over Mr. Romney once the tracking polls fully rolled over to post-convention data. Now it looks like his advantage could potentially be a bit larger than that, depending on how long the bounce holds. Despite a mediocre jobs report on Friday, there were no signs in the polls that Mr. Obamas bounce had immediately receded, as he gained further ground in the surveys that were released on Saturday.
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