Back during the primaries, you may recall, Hillary Clinton got a lot of grief when it turned out she had exaggerated the danger she faced when visiting Bosnia as First Lady during the 1990s. It dominated news coverage for a week and dealt her a major political setback, which is pretty typical for media coverage of exaggerations--both real and imagined. (Just ask Al Gore.)

I'm sure, then, that the talk shows will be all over this terrific piece of journalism by Alexander Burns and Avi Zenilman in Politico. On Monday, John McCain's campaign released a statement touting 300 economists who said they "enthusiastically support" the McCain economic plan. The document had already caused some whispering in the academic community, mostly about some notable and well-respected conservative economists conspicuous for their absence. But it turns out that wasn't the real story.

Burns and Zenilman had the good sense to call up some of these enthusiastic economists--and it turns out some of them aren't so enthusiastic after all:

While most of those contacted by Politico had warm feelings about McCain, many did not want to associate themselves too closely with his campaign and its policy prescriptions.

Howard Beales, an economist at George Washington University, explained that he signed the letter as "an expression of support for [McCain], not necessarily each and every detail of his plan, which I may not have had time to study closely."

Beales said he thought McCain had "a good plan," in general, and that his policy priorities were better than Obama's. In signing the letter, however, he did not intend to give a blanket endorsement to McCain's full agenda.

Professor James Adams of the Rensselaer Polytechnic Institute declined to elaborate on his decision to sign the letter. "I'm not involved in the campaign," he said. "I simply read a statement and signed on."

Constantine Alexandrakis, a professor at the University of Massachusetts-Dartmouth, expressed second thoughts about signing.

"I would describe myself as an Obama supporter," he explained. "Maybe I shouldn't have rushed into signing the letter."

Alexandrakis said he added his name in order to show his support for certain principles in McCain's plan — such as free trade and a reduction in corporate tax rates. But there are other aspects of McCain's proposal, such as his pledge to make permanent the 2001 tax cuts, that Alexandrakis opposes.

"While I do not agree with Obama's plan 100 [percent] either," he wrote in an e-mail, "I would prefer to see him being elected president."

One reason for the tepid support: The document itself is pretty vague and the McCain economics team had begun circulating it some months ago, as an affirmation of a broad conservative approach to economics. (Some of the signatories had forgotten all about it and didn't even know the statement had been released, until Politico contacted them.) Another reason, surely, is that many economists--even many conservative economists--have serious qualms about the McCain agenda, which pairs more tax reductions with vague, utterly unrealistic promises to cut spending. That's a formula for incurring huge deficits and growing the national debt to more onerous levels. 

In other words, this exaggeration actually matters.  A lot.

--Jonathan Cohn