The biggest news out of last night's GOP debate could be the hit taken by John McCain's reputation for straight talk.

For whatever reason, McCain chose to deny the undeniable: that on more than one occasion he has admitted not understanding the economy as well as he should. When the debate ended it took MSNBC no time to document the record. And a bit later, in the post-debate coffee klatsch, Chris Matthews and Howard Fineman unloaded on the Arizona senator for his fudging.

View video here.

CHRIS MATTHEWS: Now let's get a check on the truthfulness of what the candidates had to say here tonight. We turn to Hardball's David Shuster and his Truth Squad; David.

DAVID SHUSTER: Well Chris, let's start with that point Rachel Maddow was making about John McCain. John McCain was asked a question that included a quote of McCain talking about economics, and McCain denied the quote. Watch.

Cut to clip from debate.

TIM RUSSERT: Senator McCain, you have said repeatedly, quote, I know a lot less about economics than I do about military and foreign policy issues; I still need to be educated. Is it a problem for your campaign that the economy is now the most important issue, one that my your own acknowledgement you're not well-versed on?

JOHN MCCAIN: Actually, I don't know where you got that quote from.

Unfortunately for McCain, Shuster did know and told Matthews and the world.

SHUSTER: Well, actually NBC News got that quote from last month. John McCain was heard saying on December 17th in the Boston Globe and Time magazine: "the issue of economics is not something I've understood as well as I should. I've got Greenspan's book." And you heard Rachel Maddow refer to 2005, John McCain said something very similar to the Wall Street Journal in 2005 [NB: He told the WSJ's Stephen Moore: "I'm going to be honest: I know a lot less about economics than I do about military and foreign policy issues. I still need to be educated."]

A bit later, Matthews and Newsweek's Howard Fineman pummelled McCain for his misrepresentation.

CHRIS MATTHEWS: Howard, the Straight Talk Express: did it stall tonight? Was it derailed by his denial of a quote that's on the record?

HOWARD FINEMAN: I think he straight-talked himself right over that Bridge to Nowhere that he kept talking about. You can't pretend that you didn't say something that you said. You just can't. You can't wish it away, and it's an easy point for his rivals to attack.

Everybody was really nice on the stage tonight, pretty much, you know, very calm because they knew they were introducing themselves to the people. But the emails are burning up on that and several other things that McCain said, including what he said about tax cuts, and his support or lack of support for the president's tax cuts.

MATTHEWS: Well this is just the sort of thing that the Clinton organization is very good at slicing and dicing. If they get ahold of a quote like this in a general election, they'll say in the middle of an economic turmoil, David, this guy admits he's hapless.

. . .

FINEMAN: His answer on taxes is completely illogical. He said he voted against the Bush tax cuts because he was concerned about runaway spending. In the meantime, we've had seven years of runaway spending, and now he's for making the tax cuts permanent. That's just completely illogical! It makes no sense, and it's clear that he's doing it for political reasons, or it seems that way to too many people. And for the Straight Talk guy, that's not a good position to have.

—Mark Finkelstein is a NewsBusters contributing editor and host of Right Angle. Contact him at mark@gunhill.net.