From the AP:

The first poll taken after the presidential debate showed Kerry running even with Bush. The Democrat had the support of 47 percent and Bush 45 percent in the Newsweek poll. Independent candidate Ralph Nader had the backing of 2 percent.

Bush was slightly up, 49-43, in the same poll in early September and up 11 points in the Newsweek poll taken right after the GOP convention. The poll of 1,013 registered voters was taken from late Thursday to early Saturday and has a margin of sampling error of plus or minus 4 percentage points.