Obama senior adviser: Don't expect big bounce in polls from convention

White House senior adviser David Plouffe doesn't think President Obama's reelection campaign will receive a polling bounce after the Democratic National Convention.

Speaking on ABC's "Good Morning America" on Thursday, the day President Obama is set to deliver his campaign speech and a day after former President Clinton delivered his convention speech, Plouffe said he expected the race to remain tight up until Election Day.

"This is a very tight race," Plouffe said. "We've always believed that there's very little elasticity in the 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 in some battleground states. It's going to be very, very close all the way out."

Plouffe's comments come roughly a week after the Republican National Convention. Mitt Romney enjoyed a short-lived 2-point convention bounce before Obama retook the national lead, according to polling. Nevertheless, Plouffe said, Republicans missed an opportunity during their convention.

"But I think the Republicans had an opportunity last week to lay out for the American people what they would do for the middle class," Plouffe added. "Our sense is 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."