WASHINGTON -- There they go again. Or do they?

Will Mitt Romney miscount the number of unemployed, as he has before? Will President Barack Obama's dubious claim of a peace dividend, bopped down in the last debate, rise again? When Obama and his Republican challenger debate tonight, the media's fact-checking corps will be watching for problematic claims that have popped up repeatedly in the campaign, as well as brand new ones.

You can play fact-check Whac-a-Mole on debate night, too. You might have your hands full: The format, driven by questions from the audience, could shake things even looser than usual.

To be sure, you're not likely to catch one of them saying it's daytime when it's night. Shades of mistruth are more common than whoppers. Often, the offense is one of omission: an accurate as-far-as-it-goes assertion that ignores something really important, like the other side of the ledger. And, at times, the debaters tweak a statement to make it closer to right. You just never know.

To assist in armchair fact-checking, here's a guide to eight of the leading misleading statements of the campaign:

OBAMA:

* From the State of the Union on, the president has told the nation he wants to take "some of the money that we're saving as we wind down two wars to rebuild America," as he put it in the last debate. There is no such pile of cash. The wars were financed mostly with borrowing. So treating the end of wars as a financial bonanza just means continuing to go deeper in debt to fix roads, bridges and the like. The potential benefit is that borrowing is put to more use at home. But it's still borrowing.

* The president talks frequently about a plan to cut the deficit by $4 trillion. Impressive number, but it's not cut and dried. For one thing, he's banking more than $2 trillion already achieved in law, after a deal with Republicans last year. Moreover, he uses creative accounting to hide a huge cache of spending on Medicare reimbursements to doctors.

* "Gov. Romney's central economic plan calls for a $5 trillion tax cut." Here Obama uses an estimate from the Tax Policy Center, a Washington research group, that Romney's tax cuts would reduce federal revenue by $465 billion in 2015. Multiply that by 10 years -- a common budgeting procedure in Washington -- and he is in the ballpark in talking about $5 trillion. But Obama leaves out Romney's proposals to reduce or eliminate tax credits, deductions and exemptions. He is only counting half the plan. Romney has not specified what tax breaks he'd cut, opening himself to criticism that he's been stubbornly vague on vital elements of his plan. But there's no question he says he will pull some back, reducing the cost of his tax package.

* Obama has something to crow about when he talks about the auto bailout, which almost certainly saved General Motors and Chrysler. His estimate that up to 1 million jobs were saved is based on a 2010 study by the Center for Automotive Research, an industry think tank. But Obama rarely acknowledges that his predecessor, George W. Bush, began the auto bailout that he inherited and expanded. Vice President Joe Biden declared flatly in his debate last week, "We went out and rescued General Motors."

It's also not readily conceded that the government will lose billions on the deal. It's out about $1 billion on the $12.5 billion Chrysler bailout. At GM, the government is $27 billion in the hole right now on a $49.5 billion bailout. The ultimate loss will depend on the price of GM stock when the government sells its stake. Shares are trading for less than half the $53 price needed for the government to recoup all its money on the GM deal.

* The president and vice-president have both been cagey on $716 billion in Medicare cuts set in motion by Obama's health care law over 10 years. To hear Biden talk, the government took the money out of Medicare with one hand and is restoring it with the other.

Not really. The cuts are from payments to Medicare service providers, like hospitals, and some of the money is going toward improved preventive care and other benefits under the program. But most isn't. The bulk is being used to expand health care coverage for the general population. And there is no guarantee that the cuts to providers won't hurt the services they provide down the road.

ROMNEY:

* The Republican nominee has taken various shortcuts with jobless numbers, to the point of wildly misstating them at times. In the first debate, just before the improved September jobless figures came out, Romney said in one instance the U.S. has "23 million people out of work." A bit more accurately, he said earlier in the debate that there are "23 million people out of work or stopped looking for work." But even that was off by close to 9 million.

In all, the government counts nearly 12.1 million unemployed, 8.6 million working part-time for economic reasons and 2.5 million discouraged people who want work and looked for a job in the past year but aren't looking now.

* Romney's vow to "get us to a balanced budget" is notably short of specifics and complicated by proposals in his agenda that conflict with that goal. He promises, at once, to cut taxes, restore Medicare cuts, spend more on the armed forces -- and balance the budget by 2020. He's laid out an ambitious goal of bringing federal spending below 20 percent of the economy, but he's provided only a few modest examples of the massive cuts that would be needed. He's steering clear of proposals to touch the huge entitlement programs in the short run. Nor will he say which of the big, popular and expensive deductions and exemptions he'd pull back in the tax code.

* Romney continually portrays Obamacare as a budget-buster although the nonpartisan Congressional Budget Office has consistently said the law actually will reduce the deficit. This is more than an unsupported slam on the health care law itself. It also goes to Romney's promise to balance the budget. He suggests that repealing the law will help him get to black ink. "Obamacare adds trillions to our deficits," he said earlier in the campaign. He was a bit more circumspect in the first presidential debate, saying, "Obamacare's on my list" of things to roll back to make government more efficient.

Romney's claim is further complicated because he would negate one big money-saver in the law, the $716 billion in Medicare spending cuts he promises to restore.

He's also made selective use of forecasts about how many people will continue to have job-based health insurance. The Congressional Budget Office "says up to 20 million people will lose their insurance as Obamacare goes into effect," he stated in the last debate.

If he makes that claim again, consider that he was citing the worst-case scenario among four sketched by the budget office. Its best-case scenario was that 3 million people actually might gain coverage at work. And the estimates concern employer-provided insurance, not how many people are insured overall. Those who might lose their plans at work have other options under the law, although employer coverage would remain the mainstay for Americans age 64 and younger.