Fueled by emotional appeals from high-profile surrogates, John McCain and Barack Obama scoured for votes yesterday across a wide swath of America as swarms of presidential partisans prepared for a final weekend push before Election Day.

In Columbus, Ohio, where he trails in all public polls, McCain received a rousing introduction from California Gov. Arnold Schwarzenegger as the nominee closed out a daylong bus trip through the state. With movie-star presence, Schwarzenegger implored voters to side with McCain.

"We don't have to worry: 'Is he ready to be president of the United States?' " said Schwarzenegger, who did similar duty in 2004 for President Bush. "John McCain has served his country longer from a POW camp than his opponent has served in the United States Senate."

Obama dispatched Al Gore to Florida — a merging of man and state that served as painful symbolism to Democrats of the need to cast every ballot.

"Vote early. Take people with you to the polls," the former vice president said at a rally in Coconut Creek. Gore's 2000 campaign foundered in Florida after ballot problems led to a long legal stand-off. The Supreme Court ultimately sided with Bush, giving him the presidency with a 537-vote margin in Florida.

"Make sure," Gore said, "that every vote is voted."

Throughout the day, McCain was on the offensive and Obama was trying not to offend, attitudes that illustrated the placement of the candidates with four days left before the close of polls Tuesday night.

Obama, who made a nostalgic stop in Iowa before campaigning in usually Republican Indiana, continues to hold on to a lead in national surveys and in key state polls.

A survey of advertising for the third week of October found that the candidates spent $38 million on television. The Democratic senator from Illinois was outspending Republican McCain 3 to 1. More than 70 percent of the ads were airing in states that Republicans have reliably won — and where McCain is struggling.

The total, analyzed by the University of Wisconsin-Madison's advertising project, did not include millions more spent by Obama for Wednesday's 30-minute ad, seen by more than 33 million people.

HITTING BUSH STATES

The straits for McCain could be seen in campaign travel, too: Both candidates were dashing across states won by Bush in 2004.

Indeed, Obama intends to spend the rest of the campaign in Bush states — including Indiana, Nevada, Colorado, Missouri, Ohio, Florida, North Carolina and Virginia. McCain must win virtually all of them to reach the 270 electoral votes needed to win the presidency. McCain also plans to campaign largely in Bush states, with the notable exceptions of Pennsylvania and New Hampshire.

Schwarzenegger, who on Thursday said that McCain faces "a very tough uphill battle," yesterday cast the Arizona senator as prepared to confound such dire predictions. But the site only underscored the difficulties: Their appearance at Nationwide Arena drew what was a large crowd for McCain, but about half the arena was empty. Four years ago, when Schwarzenegger campaigned in the same venue for Bush, the arena was packed to capacity with about 20,000 supporters.

Schwarzenegger long has sponsored the annual Arnold Classic sports festival in Columbus, and joked that he hoped to invite Obama next time because "he needs to do something with those skinny legs."

"We're going to make him do some squats, and then we're going to give him some bicep curls to beef up those scrawny little arms. But if you only could do something about putting some meat on his ideas," Schwarzenegger said.

"Sen. McCain, on the other hand, is built like a rock."

Much of McCain's pitch yesterday centered on the economy and particularly the job losses that have hit Ohio and other states hard.

In Hanoverton, McCain promised to "take care of the working people devastated by the excesses and greed of Wall Street and Washington" and said he would root out corruption in the capital. At one point, he alluded to the recent conviction on corruption charges of Alaska Sen. Ted Stevens, a Republican.

"We just had a senior member of the United States Senate convicted; we have former members of Congress presiding in federal prison. I will clean up this mess and make you proud again of people who serve you," McCain said, without mentioning Stevens' name.

At each event, he portrayed Obama as too liberal for American voters and said the Democrat's tax plans would weaken an already struggling economy. Obama has proposed cutting taxes for those making less than $200,000 a year, while eliminating the Bush tax cuts for families making more than $250,000 annually. McCain, who years ago opposed the Bush tax cuts, favors making them permanent.

ON THE 'LOW ROAD'

For his part, Obama issued a pre-emptive challenge to any last-days criticism from McCain, denouncing what he described as the Republican's "low road" campaign.

In Des Moines, he recounted McCain's pledge in his 2000 campaign to "not take the low road to the highest office in this land." But, Obama said, McCain had chosen a different route this year. He called on Iowans to "beat back this kind of politics" once and for all.

Obama's visit was a bookend of sorts; his struggle for the Democratic nomination opened with a smashing victory in the snowy Iowa caucuses. On an improbably warm and sunny Halloween, he stressed the same themes he evoked in his caucus night victory speech.

"We have the chance to prove that the one thing more powerful than the politics of 'anything goes,' the one thing the cynics didn't count on, is the will of the American people," said Obama, speaking to 25,000 supporters in a downtown plaza.

But he also continued to hammer McCain on the economy and what he described as the Republican's inability to veer from the course set by Bush.

"When it comes to the economy, when it comes to the central issue of this election, the plain truth is that John McCain has stood with President Bush every step of the way," he said.