Mr. McCain has found relatively small crowds  particularly compared with those that are turning out for Mr. Obama  even as he has campaigned in battleground states.

His campaign has become embroiled by infighting, with signs of tension between Mr. McCain’s advisers and Ms. Palin’s staff, and subject to unusual public criticism from other Republicans for how his advisers have handled this race.

Republicans and Democrats said there were signs that two states that had once appeared overwhelmingly Republican, Georgia and South Carolina, were tightening, in part, because of surge of early-voting by African-Americans. An Obama win in the states seemed unlikely  and no plans were immediately on his itinerary to travel to them  but it is a sign of how volatile a year this is that more states would seem to be coming into play, rather than being settled, as the election approaches.

Mr. McCain’s aides said they remained confident that they could win. They said their candidate did not plan to introduce any kind of formal closing speech, the way Mr. Obama is doing, but would instead hammer home the issues of taxes and spending they said appeared to be giving them some steam.

“We feel good that when people hear the message about spreading the wealth versus raising taxes , they respond,” said Nicolle Wallace, a senior McCain adviser. “It’s just a matter of whether, given Obama’s saturation paid advertising, we can get the message out there.”

The contours of these final days suggest a culmination of a strategy that Mr. Obama’s advisers put in place at the beginning: to use his huge fund-raising edge to try to put as many states in play as possible and overwhelm Mr. McCain in the final days of the race.

Image Senator John McCain campaigned at the University of Northern Iowa in Cedar Falls on Sunday. Some Republicans questioned the wisdom of his campaigns spending time in the state. Credit... Stephen Crowley/The New York Times

“It’s now a big map, so you have to be in a lot of states over the last eight days,” said David Plouffe, Mr. Obama’s campaign manager.