The New York Times dramatically slashed its normal rates for a full-page advertisement for MoveOn.org's ad questioning the integrity of Gen. David Petraeus, the commander of U.S. forces in Iraq.

Headlined "Cooking the Books for the White House," the ad which ran in Monday's Times says Petraeus is "a military man constantly at war with the facts" and concluded - even before he testified before Congress - that "General Petraeus is likely to become General Betray Us."

According to Abbe Serphos, director of public relations for the Times, "the open rate for an ad of that size and type is $181,692."

A spokesman for MoveOn.org confirmed to The Post that the liberal activist group had paid only $65,000 for the ad - a reduction of more than $116,000 from the stated rate.

A Post reporter who called the Times advertising department yesterday without identifying himself was quoted a price of $167,000 for a full-page black-and-white ad on a Monday.

Serphos declined to confirm the price and refused to offer any inkling for why the paper would give MoveOn.org such a discounted price.

Citing the shared liberal bent of the group and the Times, one Republican aide on Capitol Hill speculated that it was the "family discount."

"I'm surprised they had to pay anything at all for the ad," the GOP staffer said. "They could have just asked the editorial page to run it and it wouldn't have cost them a cent."