09/10/2008 - The post-convention polls are in and they show John McCain getting quite a bounce from his convention. He not only wiped out the lift in the polls that Barack Obama got from his convention, but he is now polling better than he has at any point this year in most surveys.
The CBS poll, which was conducted from Sept. 5 to Sept. 7, has Mr. McCain at 46 percent and Mr. Obama at 44 percent among a national sample of registered voters. Prior to the conventions that poll tipped to Mr. Obama — 45 percent to 42 percent. The ABC/Washington Post survey taken at the same time shows a similar trend. And the Gallup surveys show an even more pronounced gain in support for the Republican candidate among registered voters, with Mr. McCain leading with 50 percent to Mr. Obama’s 46 percent. Other national polls also show movement in a Republican direction. There is little doubt that the fall election campaign begins in earnest with Mr. McCain having gained the momentum.
The question is, how good an indicator is this of where the electorate is headed on Nov. 4? A historical look at recent elections shows mixed results. In five of the seven elections since 1980, the candidate with the lead in early September went on to victory in November. In only two elections did the leading candidate go on to lose the election. But the record also suggests that when there was a change in momentum, in three cases that candidate won the election, and in two he was defeated.
Read the full commentary The Bounce Effect on The New York Times Web site.