Trying to make sense of all the mudslinging? Here's a handy summary of our fact-checks on the attacks.
We compare the candidates' records on the Truth-O-Meter. Paul and Romney lean toward True; Bachmann and Gingrich lean False.
The former Massachusetts governor has a relatively even PolitiFact record, about the same number of ratings at the True end of the spectrum as on the False end.
As Newt Gingrich rose in the polls, his record on the Truth-O-Meter plummeted.
The Texas governor is famous for his bold statements. But our Truth-O-Meter report card shows many of them are often wrong.
We assess Ron Paul's record on the Truth-O-Meter. Overall, his record leans toward truth.
The former Pennsylvania senator has been rated 13 times, usually earning a Half True or lower.
When we've checked former Utah Gov. Jon Huntsman, he's typically earned a Half True or higher on the Truth-O-Meter.
In the first of a series of report cards on the Republican presidential candidates, we review Michele Bachmann's record on the Truth-O-Meter.
Readers and bloggers didn't like our choice for Lie of the Year. Here is a sampling of their responses.
We respond to criticism about our 2011 Lie of the Year.
Newt Gingrich says it's against the law. We check the rules and end up throwing some britches on the yule log.
In campaign ads, web videos and TV interviews, Democrats repeatedly said House Republicans had "voted to end Medicare." Our 2011 winner is the latest in a long history of scare tactics aimed at senior citizens.
The claim that economic stimulus created "zero jobs" was the No. 1 choice of PolitiFact readers.
For the first time, PolitiFact editors and readers chose different claims as the Lie of the Year.
At the final Iowa debate, Rep. Michele Bachmann said that at the last debate, PolitiFact "came out and said that everything I said was true." Actually, she earned a Pants on Fire.
With the candidates meeting for the 16th debate tonight, we review our most interesting fact-checks from the previous 15.
It may not be remembered as long as the Lincoln-Douglas debates on which it was modeled, but we found some interesting claims to check.
He says entry-level janitors in New York make twice what entry-level teachers make. We put his claim to the Truth-O-Meter.
The Republican candidates discussed the economy, immigration -- and a $10,000 bet. We put some of their claims to the Truth-O-Meter.
The Texas governor says in a TV ad that it's wrong that "gays can serve openly in the military but our kids can't openly celebrate Christmas or pray in school." We examined his claim about prayer and Christmas and rated it False.
We don't usually check comedians, but a factual claim by Jon Stewart piqued our interest. Did Congress often work on Christmas? We put his claim to the Truth-O-Meter.
Our Readers' Choice Award has prompted lots of discussion, as Rep. Paul Ryan and others urge their supporters to vote. Polls close at 5 p.m. Eastern time on Friday.
Newt Gingrich says President Obama is killing jobs. We put the claims to the Truth-O-Meter.
The U.S. Chamber of Commerce has launched its year-long advertising blitz targeting foes such as U.S. Sen. Sherrod Brown. We put the claims to the Truth-O-Meter.
We'll soon be naming our winner. Vote now in our Readers' Choice poll!
Presidential hopeful Newt Gingrich made some extraordinary claims about food stamps. We check them out.