There was less than ten hours to go and Barack Obama was already on his way. The lecterns were in position, the TV airtime cleared, and the studio audience was wondering whether there was any point in turning up.

The most eagerly awaited presidential debate in a generation was already one of the most dramatic even before the candidates had uttered a word.

Only after mounting anger at his pledge to skip the event did John McCain make the 11th-hour decision to rush from Washington to Mississippi.

His campaign announced that he would be at the event even though Congress had not reached a deal on a financial rescue package for Wall Street — something that Mr McCain had said on Thursday night was a condition for his attendance.

The suspense over whether the first presidential debate would go ahead had greatly intensified by yesterday morning, in a game of high-stakes brinkmanship between the candidates. The build-up to the event prompted analysts to suggest that the television audience could exceed the record 80.6 million who watched Ronald Reagan and Jimmy Carter in 1980.

Mr McCain declared on Wednesday that he would suspend his campaign until a financial rescue package had been agreed upon on Capitol Hill. Yet just after 11am yesterday — and with a deal still elusive — his aides announced that he was resuming his election activities and that the debate was back on.

“He is optimistic that there has been significant progress toward a bipartisan agreement now that there is a framework for all parties to be represented in negotiations,” the McCain campaign said in a statement. Both he and Mr Obama said they would return to Washington after the debate, which had been due to focus on foreign policy but will also dwell heavily on the economic crisis.

Accompanied by his wife, Cindy, Mark Salter, a senior aide, and Rudy Giuliani, the former New York Mayor and one-time presidential rival, Mr McCain sped by motorcade from his home in Virginia to his waiting campaign plane at Washington’s Reagan airport. A travelling reporter described the atmosphere as “utter confusion”.

Meanwhile, TV networks cut from the talks on Capitol Hill to declare that “the debate is on”, with one presenter saying: “I am just being informed, Barack Obama’s plane is wheels up. He is on his way to Mississippi.”

Just before noon, Mr Obama landed in Memphis to begin the 75-minute drive to Oxford. Earlier, a charter plane had flown his team to Memphis, including David Plouffe, his campaign manager, David Axelrod, his chief strategist, and Susan Rice and Mark Lippert, senior foreign policy advisers.

Mr McCain had been under mounting pressure to attend the debate from all sides, even from members of his own party. At the University of Mississippi, where preparations for the debate have been under way for nearly two years, the Arizona senator was losing friends and supporters at a rapid rate.

“How can you not attend a debate you agreed to come to months ago?” demanded Hume Bryant, 66, who has decided in the last 48 hours to vote for Mr Obama. “Nobody here understands this, and a lot of us are angry.” Mike Huckabee, another former Republican candidate, said it would be a “huge mistake” for Mr McCain not to attend and that he should not have caused such uncertainty. A president must be prepared to “deal with the unexpected”, Mr Huckabee said, adding: “You can’t just say, ‘World, stop for a moment. I’m going to cancel everything’.”

Mr McCain had taken a significant gamble by threatening not to attend. Mr Obama in effect called his bluff by questioning why his rival could not do two things at once: attend the debate and get involved in the financial bailout negotiations. A poll showed that voters overwhelmingly wanted the event to proceed by 60 to 22 per cent.

Frank Fahrenkopf, co-president of the Commission on Presidential Debates, made it clear that it would be illegal under federal tax and election laws for the debate to proceed with Mr Obama alone. “This is causing some great consternation,” Mr Fahrenkopf said.

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