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David Plouffe, the architect of President Obama's 2008 campaign, told me this morning on "Good Morning America" not to expect a significant post-convention bounce in the polls for President Obama.

"Listen, this is a very tight race," the White House adviser said. "We've always believed that there's very little elasticity in this election. I don't think you should expect a big bounce. I think this is a race where we've got a small but important lead into battleground states.

"It's going to be very, very close all the way out but I think the Republicans had an opportunity last week to lay out for the American people what they would do for the American class. Our sense is that they missed the mark, so we think we're making a lot of progress this week but, again, you're not going to see big bounces in this election. I think for the next 61 days it's going to remain tight as a tick."

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Historically, candidates see a positive jump in the polls after conventions, but this year could be different. After the Republican National Convention in Tampa, Fla. last week, Gallup did not detect a bounce for GOP presidential nominee Mitt Romney. It is also possible that Plouffe is simply considering the optics of the situation. If the president does not receive a bump, it will appear as if the campaign expected it. If the president does get a bump, it could be characterized as a unexpected surprise.

President Obama will formally accept the nomination from the Democratic Party for a second presidential term this evening in Charlotte, N.C., at the Time Warner Cable Arena, which seats about 15,000 people. The president was initially slated to speak at the Bank of America Stadium, which seats nearly 75,000 people, but the location was shifted Wednesday ostensibly because of the threat of storms. During my interview with Plouffe, he dismissed the suggestion that the venue the changed because Democrats were struggling to fill all the seats at the original speech location.

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"Well, that's just preposterous. We were going to have a sold-out crowd and then probably people in an overflow room but the weather is what it is and we couldn't take a chance with people's safety," Plouffe said. "We knew it was a possibility when we made the decision to locate the convention here and plan to do the speech outside but we always had a contingency plan and I think what the American people are less interested in is where the president is going to give his speech than what he's going to say tonight."

Plouffe also defended the president's first term when I asked him about Bob Woodward's latest book, which chronicles the failure of President Obama to reach a debt-reduction deal with House Republicans.

"Well, I'd step back and say we worked with the Republicans in Congress when they're willing. We've cut taxes for the middle class. We've cut over a trillion dollars in spending, more than was called for in the Bowles-Simpson plan, we've helped our entrepreneurs, so we've worked with them on important things," Plouffe said.

"Obviously, we tried to reach a deficit deal with the Republicans. We got very close and didn't get there. I think this election is going to make clear, I think, to the country and hopefully to members of Congress that we're willing to do a lot of tough things - cut further spending, reform entitlements in the right way - but asking a little more from the wealthy has to be part of the answer."

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