Five days from US elections, President Barack Obama's Democratic allies got more bad news Thursday in a new poll that found his winning 2008 coalition had fractured amid deep anger at the economy.

As each side unleashed a barrage of brutal last-minute television ads, Democrats enlisted former president Bill Clinton to make the difference in some nail-biter contests while Republicans used Obama's own words against him.

And with the 2012 White House race set to start in earnest shortly after the election, Republican former vice presidential hopeful SarahPalin said in a television interview that she would run "if there's nobody else to do it."

Palin, who has criss-crossed the United States stumping for Republican candidates, told the Hollywood-focused Entertainment Tonight program she would take "a real close look at the lay of the land" before deciding.

Fired-up Republicans were widely expected to net more than the 39 seats they needed to take over the House of Representatives but fall short of the 10 seats they needed to recapture the Senate.

A new survey by The New York Times and CBS television found that, by a broad 61-34 margin, respondents believed that the country was on the "wrong track" as it struggled to emerge from the worst economic downturn since the 1930s.

The survey, which had an error margin of plus or minus three percentage points, found that Republicans had wiped out the Democratic edge with women, Roman Catholics, less affluent Americans and independents, key to Obama's victory in 2008 and the Democratic capture of Congress in 2006.

While Democrats have beaten Republicans among women voters since 1982, Republicans held a four-percentage-point advantage in the final campaign sprint, and a 47-32 percent edge with independents who often sway US elections.

The poll found nearly two in three respondents willing to back political newcomers on November 2, and 28 percent more ready this year to back someone with views that "seem extreme."

Obama planned an 11th-hour coast-to-coast campaign blitz through key battlegrounds, while Clinton lent his political star-power to Democrats in tight races, notably looking to pump up the party's get-out-the-vote efforts.

The former president was to attend three rallies with Democratic Representative Joe Sestak, who was locked in a bitter too-close-to-call Senate battle with Republican Pat Toomey in Pennsylvania.

In Nevada, Democratic Senate Majority Leader Harry Reid blistered Republican rival Sharron Angle with a television advertisement accusing her of leaving children at the mercy of sex offenders, dooming cancer patients to the grave, and shipping US jobs to China.

The commercial, which features shots of an empty playground swing and pallbearers carrying a coffin through a cemetery, also charges that Angle favored prison inmates receiving "massages in a radical Scientology program" -- a reference to a proposed treatment plan for women drug addicts behind bars.

Reid, the Republicans' highest-profile target, was locked in the fight of his political life against Angle, a "Tea Party" darling who has raised millions of dollars to unseat him.

Angle spokesman Jerry Stacy shot back that Reid "is a failed politician who is unable to run on his disastrous record, so he had to deploy a multi-million dollar campaign trying to distort who Sharron is.

"Voters in Nevada are smarter than that, and on Tuesday voters will decide they've had enough of Harry Reid and his policies of destruction," he added.

The Republican National Committee, meanwhile, released an Internet ad warning voters: "Don't wake up on November third and realize you didn't do enough" and using Obama's own hopeful words about the economy against him.

The ad juxtaposes the stubbornly high US unemployment rate of nearly 10 percent and the 13.6-trillion-dollar national debt with the president's repeated assurances that the country is going "in the right direction."

All 435 House of Representatives seats, 37 of 100 Senate seats, and 37 governorships are up for grabs in the elections.

Historically, a sitting US president's party loses seats in his first mid-term elections, but such contests have been poor predictors of chances for a second term.

Taking control of even one chamber of Congress would give Republicans broad control over the legislative agenda in Washington and new power to investigate the Obama administration and probe government programs.