President George W. Bush and Democratic challenger Mr John Kerry meet in their second face-to-face debate today with Mr Bush looking to rebound from last week's performance.
The encounter at Washington University in St. Louis follows a round of bitter campaign exchanges on the Iraq war and a climb in the polls for Mr Kerry, whose aggressive attacks put Mr Bush on the defensive in last week's first debate.
The president is under pressure to turn in a stronger debate performance and shift the focus back to Mr Kerry's voting record in the senate and what Republicans say are his shifting statements on Iraq.
"It's an opportunity for Senator Kerry to defend a 30-year record of being wrong on defence," Mr Bush's campaign manager said, adding Mr Bush also would press Mr Kerry on how he would pay for his health care plan and his various statements on Iraq.
"We're going to see a different President Bush at this debate," predicted Mr Kerry adviser Mr Joe Lockhart, who said Wednesday's harsh attack on Mr Kerry from the campaign trail was a preview of a more aggressive Bush.
Polls show the race for the White House tightening after last week's debate, with Kerry pulling close or even to Bush in most national surveys.
Mr Bush and Vice President Dick Cheney defended the invasion yesterday despite a new US report that said Baghdad had not rebuilt its program for chemical, biological or nuclear weapons after the 1991 Gulf War.
Mr Kerry said Mr Bush "aggrandised and fictionalised" the threat from Iraqi leader Saddam Hussein.