Mississippi's Republican governor, Haley Barbour, said Thursday that as far as he is concerned, the scheduled debate Friday between Sens. Barack Obama and John McCain will go on as planned. But the McCain camp has not yet committed to the event.

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"I expect there to be a debate tomorrow night and I look forward to it," he told reporters gathered at the University of Mississippi, which is to host the event. He said he had not spoken to either candidate about their plans to attend.

The two rivals, meanwhile, dug in to positions they staked out on Wednesday, with McCain saying he wants the debate postponed and Obama saying he intends to stick to the schedule.

Obama had contacted McCain on Wednesday morning to discuss a joint statement in support of a $700 billion, White House-backed bailout package aimed at stabilizing the meltdown in the nation's financial industry. He said both men agreed on some general principles regarding the package and thought a show of unity would help push the measure through Congress.

McCain returned the call in the afternoon and the two discussed the statement. But shortly after that, McCain hastily called a news conference to say he was suspending his campaign and calling off the Friday debate unless and until Congress approved the bailout. And he called on Obama to follow suit.

Obama called his own news conference later to rebuff McCain.

"This is exactly the time that the American people need a debate" between the two candidates, away from Capitol Hill, so that Americans can hear their ideas for leading the country out of the crisis," Obama said.

Both men went to Washington on Thursday, summoned by President George W. Bush, to attend a meeting with congressional leaders in hopes of securing the legislation. A tentative agreement on the deal between Republicans and Democrats was reached Thursday afternoon. They appeared with the president for a photo opportunity late in the day, where Bush said, "My hope is that we can reach an agreement very shortly."

McCain on Wednesday had called for his Democratic rival to agree to a postponement of the debate until Congress agrees on a $700 billion government plan to rescue banks from enormous debt. McCain said he was also suspending his campaign until the legislation was passed.

Later in the afternoon, Obama rebuffed McCain.

"This is exactly the time that the American people need a debate" between the two candidates, away from Capitol Hill, so that Americans can hear their ideas for leading the country out of the crisis," Obama said.

Neither men have a hand in writing the legislation, and neither sits on Senate committees that might be called to vote on the matter.

Even so, and regardless of the tentative agreement reached Thursday, the McCain camp says its candidate still won't debate on Friday unless the legislation passes.

"There's no deal until there's a deal. We're optimistic but we want to get this thing done," McCain spokesman Brian Rogers said.

"With so much on the line, for America and the world, the debate that matters most right now is taking place in the United States Capitol —- and I intend to join it," McCain said Thursday in New York.

Obama argued the debate should proceed because a president needs to be able to handle more than one issue at a time.

"Our election is in 40 days. Our economy is in crisis, and our nation is fighting two wars abroad. The American people deserve to hear directly from myself and Sen. McCain about how we intend to lead our country. The times are too serious to put our campaign on hold, or to ignore the full range of issues that the next president will face."