Mr. NYHAN: We're not exactly sure but what we think is happening is people are hearing these claims.

NPR: Campaign Attack Ads Call 'Facts' Into Question

Mr. BRENDAN NYHAN: (PhD Candidate, Duke University, Author, "When Corrections Fail: The Persistence Of Political Misperceptions"): Thank you.

NPR: Campaign Attack Ads Call 'Facts' Into Question

"Apparently his advisors feel that he will have trouble standing up under tough grilling, " said Boston Globe reporter David Nyhan.

CNN: Boston takes dig at Bush over debate

Mr. NYHAN: Well, the backfire effect we're talking about in the series of experiments that we did, we only found among conservatives.

NPR: Campaign Attack Ads Call 'Facts' Into Question

Mr. NYHAN: You know, we thought about that and actually - in our second set of experiments, we change the media source.

NPR: Campaign Attack Ads Call 'Facts' Into Question

Brenden Nyhan is a PhD at Duke University and as he told you he's a former blogger at spinsanity, a political rhetoric watchdog.

NPR: Campaign Attack Ads Call 'Facts' Into Question

Mr. NYHAN: It's incredibly depressing, and it's incredibly personally depressing for me because in the spirit of full disclosure, I should say that I used to co-edit a website called Vinsanity(ph).

NPR: Campaign Attack Ads Call 'Facts' Into Question

Mr. NYHAN: You know, I guess what I tend to fall back on right now is the idea that even if the public is hard to convince that there is something to the idea that you're embarrassing the campaigns publicly.

NPR: Campaign Attack Ads Call 'Facts' Into Question