BARACK OBAMA and John McCain meet in New York tonight for their final debate in the presidential campaign and what could be the Republican's last opportunity to alter the trajectory of the race.
Mr McCain said yesterday that he expects to raise Mr Obama's association with William Ayers, a former urban guerrilla with whom the Democrat has served on charitable boards.
The Republican said that Mr Obama had invited such a discussion by suggesting last week that Mr McCain did not have the courage to confront him directly about it.
"I was astonished to hear him say that he was surprised that I didn't have the guts," Mr McCain told a St Louis radio station.
"I think he is probably ensured that it will come up this time." In a sign that the Republican focus on Mr Ayers may at last be having an impact, the Obama campaign released a radio advert in response to them.
"Bill Ayers is a professor of education who once served with Obama on a school reform board, a board funded by conservative Republicans tied to McCain," the advert says.
"When Ayers committed crimes in the sixties, Obama was eight years old. Obama condemned those despicable acts. Ayers has had no role in Obama's campaign, and will have no role in his administration."
Mr McCain has said he is less interested in "an old washed-up terrorist" than in whether Mr Obama has been truthful about his relationship with Mr Ayers.
Tonight's debate at Hofstra University on Long Island comes as polls show Mr Obama consolidating his lead nationally and in battleground states.
A new USA Today/Gallup poll puts the Democrat ahead by 51-44 and new Quinnipiac polls show him extending his lead in four key states.
According to the polls, Mr Obama is now ahead by nine points in Colorado, 11 in Minnesota, 16 in Michigan and 17 in Wisconsin.
Mr Obama is now ahead in all the major battleground states, including Ohio, Florida, Pennsylvania, Nevada and Virginia.
Mr McCain yesterday proposed a new $52.5 billion economic plan that would abolish taxes on unemployment benefits and cut the capital gains tax and promised to guarantee all bank deposits for at least six months.
Speaking in Blue Bell, Pennsylvania, Mr McCain said he could offer strong leadership on the economy and warned against turning the country over to Mr Obama.
"He is an eloquent speaker, but even he can't turn a record of supporting higher taxes into a credible promise to cut taxes. What he promises today is the opposite of what he has done his entire career. Perhaps never before in history have the American people been asked to risk so much based on so little," Mr McCain said.
"My plan for economic recovery does not require guesswork or blind faith from the American people. You know my record.
"You don't have to hope I will do what I promise. When I say I will cut spending, you need only look at my record to know it's true. When I say I will defend taxpayers, you know it's true because it's what I've always done."
The Obama campaign dismissed Mr McCain's economic plan as offering no help to the American middle class while bailing out Wall Street bankers.
"His plan continues to provide no tax relief at all to 101 million hard-working families, including 97 per cent of senior citizens, and it does nothing to cut taxes for small businesses or give them access to credit," said Obama spokesman Bill Burton.
"Senator McCain also shows how little he understands the economy by offering lower capital gains rates in a year in which people don't have an awful lot of capital gains. His trickle-down, ideological recipes won't strengthen our economy and grow our middle-class, but Barack Obama's pro-jobs, pro-family economic policies will."
Hillary Clinton said yesterday that the Republican campaign had "really lost its way".
Mrs Clinton told Fox News that the chances of her running again for the White House were "probably close to zero" and that she had no interest in becoming a supreme court justice, but was content to remain as a senator for New York.
