Barack Obama and John McCain sparred over the economy, taxes and foreign policy during a spirited, 90-minute debate in Nashville that displayed clear policy differences but produced no game-changing moment for either candidate. Denis Stauntonreports from Tennessee.
The debate at Belmont University, the second of three between the presidential candidates, featured questions from 80 undecided voters in a town-hall format that saw Mr Obama and Mr McCain roaming the stage in their most intimate encounter yet.
It took place at the end of a day that saw the Dow Jones plunge to its lowest level in five years and the first half-hour was dominated by questions about the economy.
Mr McCain unveiled a new policy to deal with the crisis in the housing market, proposing that the federal government should buy bad mortgages, reset them at the diminished value of the home and negotiate with borrowers a new payment plan so they could keep their homes.
"Is it expensive? Yes. But we all know, my friends, until we stabilise home values in America, we're never going to start turning around and creating jobs and fixing our economy, and we've got to give some trust and confidence back to America," Mr McCain said.
During Mr McCain's answers, Mr Obama sat on a stool, watching the Republican and often smiling. While the Democrat was speaking, Mr McCain would look away, scribble notes and sometimes walk around the stage.
At one moment, Mr McCain's disdain for Mr Obama came to the surface when he referred to the Democratic candidate as "that one" during an exchange about their records on tax and energy.
"By the way, my friends, I know you grow a little weary of this back and forth: there was an energy bill on the floor of the Senate, loaded down with goodies, billions for the oil companies, and it was sponsored by Bush and Cheney. You who voted for it? You might never know," Mr Mc Cain said, before pointing at Mr. Obama.
"That one. You know who voted against it? Me."
Asked if health care in America was a responsibility, a privilege or a right, Mr McCain said it was a responsibility but Mr Obama insisted that it was a right.
"I think it should be a right for every American. In a country as wealthy as ours, for us to have people who are going bankrupt because they can't pay their medical bills -- for my mother to die of cancer at the age of 53 and have to spend the last months of her life in the hospital room arguing with insurance companies because they're saying that this may be a pre-existing condition and they don't have to pay her treatment, there's something fundamentally wrong about that," he said.
Mr Obama's most effective moment came after Mr McCain criticised him for suggesting that US forces could pursue Osama Bin Laden inside Pakistan without the permission of Pakistan's government. The Republican said that Mr Obama was ignoring Teddy Roosevelt's injunction to speak softly but carry a big stick.
"Now, Senator McCain suggests that somehow, you know, I'm green behind the ears and, you know, I'm just spouting off, and he's somber and responsible," Mr Obama said.
"Senator McCain, this is the guy who sang, "Bomb, bomb, bomb Iran," who called for the annihilation of North Korea. That I don't think is an example of "speaking softly." This is the person who, after we had -- we hadn't even finished Afghanistan, where he said, "Next up, Baghdad"."
The candidates rehearsed their disagreements about the Iraq war but they agreed that they would not seek United Nations approval for military action if Iran attacked Israel. Mr Obama suggested that the US should intervene militarily elsewhere to prevent genocide even if no American national security interest was at stake.
"We may not always have national security issues at stake, but we have moral issues at stake. If we could have intervened effectively in the Holocaust, who among us would say that we had a moral obligation not to go in? If we could've stopped Rwanda, surely, if we had the ability, that would be something that we would have to strongly consider and act," he said.
"So when genocide is happening, when ethnic cleansing is happening somewhere around the world and we stand idly by, that diminishes us. And so I do believe that we have to consider it as part of our interests, our national interests, in intervening where possible."
Mr McCain's chief campaign adviser Charlie Black acknowledged after the debate that it had not been a game changer in the campaign. "Fundamentally, probably not," he said. "Debates very seldom have a dramatic effect."
Mr Black insisted, however, that the debate had helped Mr McCain, despite instant polls by CNN and CBS showing that most voters believed Mr Obama had won the evening.
Mr Obama's chief strategist, David Axelrod, described the debate as "a really good discussion" but he described Mr McCain's reference to the Democrat as "that one" as a curious moment.
"I thought it was odd," he said. "Senator Obama has a name and candidates usually use their opponent's name."