Barack Obama is continuing to lead John McCain in opinion polls as the White House rivals head into their final debate tonight.
Mr McCain needs a strong performance to begin to turn around a White House race that could be slipping away.
A CBS News/New York Times poll today showed Mr Obama is leading by 14 percentage points, the fifth survey this week to register his lead in double-digits.
In another poll released today, Democrat Mr Obama leads his Republican rival Mr McCain 48 per cent to 44 per cent among likely US voters, down slightly from Mr Obama's 6-point advantage yesterday.
The Reuters/C-SPAN/Zogby poll has a margin of error of 2.9 percentage points.
Mr 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."
Mr Obama and Mr McCain meet in their third and final debate at Hofstra University in Hempstead, New York, tonight, giving Mr McCain one last chance to reshape a presidential race that appears to be tilting toward Mr Obama with less than three weeks before the November 4th election.
It will be their final opportunity to reach a television audience of 60 million or more.
"You can do yourself a lot of good when you have a debate with that many people watching," South Carolina Republican Party Chairman Katon Dawson said.
The debate comes as opinion polls show Mr Obama gaining strength nationally and in battleground states after weeks of economic turmoil and plunging stock markets, with more voters saying they trust Obama's leadership on the economy.
The Reuters/C-SPAN/Zogby poll shows Mr Obama with an 8-point edge among independents, down sharply from yesterday, 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.
Mr McCain (72) an Arizona senator, leads narrowly among men and by 14 points among whites. He reclaimed a slight lead among families with at least one member in the military.
Mr 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.
The poll, conducted between Saturday and yesterday, showed independent Ralph Nader with 2 per cent. Libertarian Bob Barr registered 1 per cent. Four per cent 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.
Mr McCain and Mr Obama are battling for the 270 electoral votes needed to win the presidency.
A separate Zogby survey found Mr McCain's surprise choice of Sarah Palin, the governor of Alaska, as his running mate made 30 per cent less likely to vote for him while 26 per cent were more likely.
The poll found 43 per cent said it would have no effect on their vote.
Mr Obama's choice of Delaware Senator Joe Biden was less controversial, with 59 per cent saying it would have no effect.
The bad poll news heightened the debate stakes for Mr McCain, who unveiled a package of measures yesterday to help investors, particularly older Americans who have seen their retirement savings decimated by stock market losses.
The Obama campaign was eager to raise the stakes for Mr McCain.
"It's his last chance to somehow convince the American people that his erratic response to this economic crisis doesn't disqualify him from being president," Obama spokesman Bill Burton said in a memo to reporters.
Mr McCain has indicated he is likely to bring up Mr Obama's relationship with former 1960s radical William Ayers. The two served on a community board in Chicago together and Mr Ayers hosted a political event for Mr Obama early in his career.
Mr Obama had noted Mr McCain's reluctance to discuss the issue with him directly during their last encounter.
"I was astonished to hear him say that he was surprised that I didn't have the guts to do that," Mr McCain said in a radio interview. "I think he's probably assured that it's going to come up this time."
Several recent polls have shown Mr McCain's attacks on Mr Obama's character have largely backfired, increasing unfavorable opinions about Mr McCain among voters looking for solutions on the economy.
"There is no question the negative campaigning just isn't working," pollster John Zogby said. "To make an impact in this debate, McCain needs to be proactive and be very specific about the way he would lead an economic recovery."
The final debate takes place at 9pm (1am Irish time). Log on to irishtimes.com tomorrow morning for Denis Staunton's report on the debate.
The bad poll news heightened the debate stakes for Mr McCain, who unveiled a package of measures yesterday to help investors, particularly older Americans who have seen their retirement savings decimated by stock market losses.
The Obama campaign was eager to raise the stakes for Mr McCain.
"It's his last chance to somehow convince the American people that his erratic response to this economic crisis doesn't disqualify him from being president," Obama spokesman Bill Burton said in a memo to reporters.
Mr McCain has indicated he is likely to bring up Mr Obama's relationship with former 1960s radical William Ayers. The two served on a community board in Chicago together and Mr Ayers hosted a political event for Mr Obama early in his career.
Mr Obama had noted Mr McCain's reluctance to discuss the issue with him directly during their last encounter.
"I was astonished to hear him say that he was surprised that I didn't have the guts to do that," Mr McCain said in a radio interview. "I think he's probably assured that it's going to come up this time."
Several recent polls have shown Mr McCain's attacks on Mr Obama's character have largely backfired, increasing unfavorable opinions about Mr McCain among voters looking for solutions on the economy.
"There is no question the negative campaigning just isn't working," pollster John Zogby said. "To make an impact in this debate, McCain needs to be proactive and be very specific about the way he would lead an economic recovery."