Democrat Barack Obama has a 4-point national lead over Republican John McCain as the White House rivals head into their final debate, according to a Reuters/C-SPAN/Zogby poll released today.
Obama leads McCain 48 percent to 44 percent among likely U.S. voters in the latest four-day tracking poll, down slightly from Obama's 6-point advantage on Tuesday. The poll has a margin of error of 2.9 percentage points.
Obama's lead in the poll has remained stable, drifting between 4 and 6 percentage points for the last week.
"It's not over, but it's not moving a lot," pollster John Zogby said. "There does not seem to be a dramatic shift going on."
Obama and McCain meet in their third and final debate at Hofstra University in Hempstead, New York, on Wednesday night, giving McCain one last chance to reshape a presidential race that appears to be tilting toward Obama with less than three weeks before the Nov. 4 election.
Some other national polls in the last few days have shown Obama with a double-digit lead on McCain, fueled by perceptions Obama would do a better job managing the faltering economy and unhappiness with McCain's attacks on him over the past week.
The Reuters/C-SPAN/Zogby poll shows Obama with an 8-point edge among independents, down sharply from Tuesday, and an 8-point lead among women, two key swing voting blocs.
Both candidates have solidified their base support, winning nearly nine of every 10 votes from members of their own party.
McCain, 72, an Arizona senator, leads narrowly among men and by 14 points among whites. The former Navy pilot and prisoner of war in Vietnam reclaimed a slight lead among families with at least one member in the military.
Obama, 47, an Illinois senator who would be the first black president, wins nine of every 10 black voters and solid majorities of Hispanics, Catholics and Jewish voters.
Zogby said McCain has been stuck at about 44 percent in more than a week of polling. Obama has lingered at about 48 percent for most of the week, hitting 49 percent twice but never breaking 50 percent.
The poll, conducted Saturday through Tuesday, showed independent Ralph Nader with 2 percent. Libertarian Bob Barr registered 1 percent.
Four percent of voters said they were still undecided.
The rolling tracking poll surveyed 1,210 likely voters in the presidential election. In a tracking poll, the most recent day's results are added while the oldest day's results are dropped in an effort to track changing momentum.
McCain and Obama are battling for the 270 electoral votes needed to win the presidency.