obama_mccain_4.jpgWASHINGTON (AP) _ Republican John McCain dialed back personal attacks on Democrat Barack Obama over the weekend, but vowed he would “whip'' his opponent's “you know what'' when they clash this week in their final presidential debate on Wednesday.

With three weeks remaining until election day, McCain is trailing in the polls and struggling under the heavy burden of his association with Republican President George W. Bush _ and the blame that attaches to the incumbent Republicans for the crumbling financial markets.

Last week, both McCain and running mate Alaska Gov. Sarah Palin appeared to be trying to shift attention away from the troubles confronting the American voters by issuing stinging attacks on Obama.

Palin opened the series of blistering assaults by accusing Obama of “palling around with terrorists.''

On Sunday, one man shouted out “Obama loves terrorists'' as Palin talked about “the bad guys.''

But as the polls showed Obama widening his lead, the Republicans apparently decided the tactic had proven fruitless and shifted course back to vows to revamp Washington, blaming politicians and greedy Wall Street executives for the worst financial crisis to face the country in 80 years.

Palin campaigned in southeastern Ohio on Sunday, easing back on attacks but reminding the crowd of Obama's remarks during the primary campaign in which he said working class Americans, afraid for their economic future, were clinging to guns and religion.

The economy, the dominant issue in the presidential campaign for weeks, has now become a voter obsession as the stock market plummets and vital sources of credit remain frozen.

With retirement savings vanishing in the stock market plunge, tens of thousands of homeowners facing mortgage foreclosure and unemployment rising, McCain's campaign handled the financial crisis unevenly. His first response to news of the threatened financial meltdown was to declare that the country's economic fundamentals were in good shape.

McCain interrupted his debate preparations Sunday to tell several dozen volunteers at his campaign headquarters outside Washington that Obama was in for some of his signature “straight talk.''

“We're a couple points down, OK, nationally, but we're right in this game,'' the veteran Arizona senator said to cheers. “The economy has hurt us a little bit in the last week or two, but in the last few days we've seen it come back up because they want experience, they want knowledge and they want vision. We'll give that to America.''

McCain said he and Palin would continue campaigning hard until Election Day. The two planned a joint appearance Monday in Virginia, a Republican stronghold turned battleground state.

“We're going to spend a lot of time and after I whip his you-know-what in this debate, we're going to be going out 24/7,'' McCain said.

McCain also needs to do more to distance himself from Bush, his supporters believe.

“He has to make the case that he's different than Bush and better than Obama on the economy,'' former House Speaker Newt Gingrich said in an interview. “If he doesn't win that case, it's all over, and it's going to be a very bad year for Republicans.''

Obama also was in Ohio on Sunday, and took a break from debate preparations to walk around a neighborhood in the town of Holland, near Toledo, to talk to voters. He was repeatedly asked what he could do to help struggling families.

His answers ranged from tax cuts to aid for struggling auto companies to measures to reduce home foreclosures.

Denise Knisley, a 53-year-old grocery store employee, said she had been thinking about voting for the Democrat and definitely will after meeting him.

“He sounds really positive, like he's going to help us,'' Knisley said. “You've got to believe in somebody.''

Obama's fortunes got a further boost Sunday when former President Bill Clinton and his wife, Sen. Hillary Rodham Clinton, made their first joint campaign appearance together on the Illinois senator's behalf. Bill Clinton had held back all-out support, apparently harboring hard feelings from the Democratic primary contest in which Obama outdistanced the former first lady in a bitter, extended race.

Bill Clinton primarily extolled the virtues of his wife, but urged voters to back Obama, who he said would put an end to Republican bumbling that he blamed for the failing economy.

“If you ask yourselves who has the best ideas, who's got the best instincts, who's got the best ability to understand these challenges, who's got the best supporting cast, the answer is Barack Obama,'' the former president said.

Hillary Clinton introduced Obama's running mate, Delaware Sen. Joe Biden, at the Sunday rally in working-class Scranton, Pennsylvania, a city that has taken on outsized symbolism for Democrats this year. It was Biden's birthplace and Hillary Clinton's father grew up and is buried there.

Her spirited remarks were repeatedly interrupted by applause from thousands of supporters as she delivered one-liners attacking Bush and McCain. At one point she said Republicans viewed middle class Americans not as “fundamental, but ornamental'' to the functioning of the U.S. economy.

“They don't understand that we are at the core of whether this country goes up or down,'' she said, stretching the facts to include herself and her husband, both who have become wealthy, in with the middle class.

Biden hammered McCain as the candidate who would only bring the country four more years of Bush administration policies, dismissing both men as unable to deal with the failing economy. He charged McCain with trying to distract Americans from their economic woes by launching “unbecoming personal attacks'' on Obama.

“Every single false charge, every single baseless accusation is a simple attempt to get you to focus on something other than what's affecting your family and your country,'' Biden said.

After pointedly saying McCain had been “erratic'' in his response to the U.S. financial crisis, he said: “We need more than a brave soldier, we need a wise leader.'' McCain spent 5 1/2 years in a North Vietnamese prison after being shot down while on a bombing run.