KEY POINTS:
After weeks of flinging mud at each other on the campaign trail, senators Barack Obama and John McCain are preparing for what could turn into a seminal moment in the election, a televised debate watched by a huge national audience.
With the race for the White House neck-and-neck and the financial markets in turmoil, interest in the debate, being held in Oxford, Mississippi, is expected to be unprecedented.
The stakes are especially high for Obama, whose prickliness and long-windedness make him an easy target for his rival.
McCain has a well-deserved reputation for slamming his opponents while tap-dancing his way out of tricky situations. The former fighter pilot relishes the give-and-take of single combat.
One of McCain's favourite tactics in debate is simply sitting grinning to the cameras while his rivals say their piece.
The danger that Obama's advisers see is that their candidate will fall into an all-too-familiar mode of lawyer and law professor.
This week Obama is holed up at a special "debate camp" in Tampa, Florida, where one of his few grey-haired advisers, hard-nosed Washington lawyer Greg Craig, is sparring with him.
Another practice opponent is Ron Klain, who was part of the team that helped John Kerry and Al Gore prepare for debates during their failed presidential bids. Kevin Spacey played him in the movie Recount, about the 2000 Florida "hanging chad" debacle.
McCain's campaign isn't saying who he will use for sparring practice, but he is being advised by Brett O'Donnell, a champion debating coach from televangelist Jerry Farwell's Liberty University.
The campaign angrily repudiated an earlier report that it was using a prominent black Republican, Michael Steele, to play Obama in practice debates.
The first debate will focus on foreign policy, widely acknowledged to be McCain's strongest suit.
Obama dislikes the informality of televised exchanges and considers the rapier-like quips and sound-bites to be a distraction from the important task of healing America's multiple problems.
Many voters are only tuning into the election at this late stage, however, and the history of presidential election debates shows that a candidate's likeability is often more important than his experience or stance on the issues.
McCain has the instincts of a street fighter and is capable of trapping his adversary and plunging a rhetorical knife between his ribs.
That is how he emasculated Mitt Romney in a Republican primary debate this year. "Well, Governor," he exclaimed in a voice dripping with condescension, "I'm astounded that you haven't found out what waterboarding is", turning the debate towards his own experiences when he was a prisoner of war.
McCain's contempt for an adversary whom he does not believe has paid his dues is scarcely disguised and he is expected to provoke him to expose his weaknesses.
The Obama campaign is deeply wary of the coming encounter.
"Despite the fact that we got the chance to do this a lot during the primaries, these debates are not by any stretch of the imagination his strong suit," said Robert Gibbs, a senior strategist. "He likes to talk about a problem, give some examples that address some solutions and oftentimes that doesn't fit into the moderator's allotted time."
That may be exactly what the McCain camp is hoping for.
Over the gruelling months on the campaign trail, Obama has hardly improved from one of his worst moments during a debate with other Democrats when they were asked how they would deal with terrorists.
"Let's do everything we can to destroy them," responded Senator Hillary Clinton.
When his turn came, Obama rambled on about engaging the international community and asked for a second chance to reply.
- INDEPENDENT
GOING HEAD TO HEAD
WHERE THEY STAND
AFGHANISTAN
John McCain: Favours unspecified boost in United States forces.
Barack Obama: Would add about 7000 troops to the US force of 36,000, bringing the reinforcements from Iraq. Has threatened unilateral attack on high-value terrorist targets in Pakistan as they become exposed, "if Pakistan cannot or will not act" against them.
CUBA
McCain: Ease restrictions on Cuba once US is "confident that the transition to a free and open democracy is being made".
Obama: Ease restrictions on family-related travel and on money Cuban-Americans want to send to their families in Cuba. Open to meeting new Cuban leader Raul Castro without preconditions. Ease trade embargo if Havana "begins opening Cuba to meaningful democratic change".
IRAN
McCain: Favours tougher sanctions, opposes direct high-level talks with President Mahmoud Ahmadinejad.
Obama: Initially said he would meet Ahmadinejad without preconditions, now says he's not sure "Ahmadinejad is the right person to meet with right now". But says direct diplomacy with Iranian leaders would give US more credibility to press for tougher international sanctions. Says he would intensify diplomatic pressure on Tehran before Israel feels the need to take unilateral military action against Iranian nuclear facilities.
IRAQ
McCain: Opposes scheduling a troop withdrawal, saying latest strategy is succeeding. Supported decision to go to war, but was early critic of the manner in which Administration prosecuted it. Was key backer of the troop increase. Willing to have permanent US peacekeeping forces in Iraq.
Obama: Spoke against war at start, opposed troop increase. Voted against one major military spending bill in May 2007; otherwise voted in favour of money to support the war. Says his plan would complete withdrawal of combat troops in 16 months.
TIME TO CRAM
OBAMA
Three days of debate preparations with aides in a Florida hotel. Among the staff helping are senior advisers David Axelrod, Anita Dunn and Robert Gibbs, with Washington lawyer Greg Craig playing the role of McCain. Craig, a foreign policy expert and member of President Bill Clinton's impeachment defence team, also played President George W. Bush in Senator John Kerry's preparations in 2004.
McCAIN
Plans to work with advisers on the debate between campaign events this week in Ohio and Michigan, meetings with world leaders in New York for the United Nations General Assembly and briefings on the Wall Street crisis. He also plans to meet Bono, the rock star and humanitarian, and appear on TV's Late Show with David Letterman.
- AP
