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TEXAS - Republican John McCain and Democrat Barack Obama faced off overnight, in a possible prelude to a US presidential election battle, tangling over whether Iraq would be prey for al Qaeda if US troops are withdrawn.
Democrat Hillary Clinton, who needs big wins in Texas and Ohio next Tuesday to salvage her struggling candidacy, declared herself optimistic about her chances following her final debate with Obama, on Tuesday night in Cleveland.
"What keeps me optimistic is the success I've had thus far and what I think the prospects are for Tuesday. People have just been really rallying to my candidacy," she told reporters on her campaign plane before an event in Zanesville, Ohio.
But McCain, an Arizona senator who at 71 would be the oldest person ever elected to a first presidential term, and Obama, the Illinois senator who at 46 would be one of the youngest, looked past Clinton and quarrelled anew over the war in Iraq as it approaches its fifth anniversary.
The unpopular war is an important fault line in the campaign for the November presidential election, with Democrats advocating a quick US troop withdrawal while McCain insists a pullout would amount to surrender and give Islamic extremists a victory.
McCain, an Arizona senator who has linked his candidacy to a successful outcome in Iraq, pounced on Obama at a town hall meeting in Texas as he seeks to wrap up the Republican presidential nomination.
Obama said during the debate with Clinton that once he withdrew US troops from Iraq, if al Qaeda were to form a base there, "then we will have to act in a way that secures the American homeland and our interests abroad."
"I have some news," McCain said. "Al Qaeda is in Iraq. It's called Al Qaeda in Iraq. My friends, if we left they wouldn't be establishing a base, they'd be taking a country and I'm not going to allow that to happen."
McCain was somewhat undermined by Director of National Intelligence Michael McConnell, who told US lawmakers Wednesday that Al Qaeda in Iraq had suffered major setbacks last year and although still "capable of mounting lethal attacks," the group had suffered hundreds of members killed or captured.
Obama hit back at a rally in Columbus, Ohio, saying McCain had joined with President George W Bush in supporting a war "that should have never been authorised and should have never been waged."
"I have some news for John McCain, and that is that there was no such thing as al Qaeda in Iraq until George Bush and John McCain decided to invade Iraq," he said to cheers.
He mocked McCain for his oft-repeated remark that he will get al Qaeda leader Osama bin Laden if he has to follow him to the "gates of hell."
"So far all he's done is follow George Bush into a misguided war in Iraq," Obama said.
Clinton was pushing economic themes in Ohio, a state that has lost 23 per cent of its manufacturing jobs since 2000 and which the subprime mortgage crisis has hit hard, with foreclosures climbing 88 per cent in 2007.
"The economy is the number one issue in the country and it's unbelievably important here in Ohio," she said. "We're sliding into a recession and the price of everything is going up at the same time."
Clinton, a New York senator who would be America's first woman president, has lost the last 11 state contests to Obama.
"What keeps me going is that I know I would be the best president. I know that I could handle the problems we have here at home and around the world. I have no doubt about that," she said.
- REUTERS