At a Christmas party for the press two months ago, Jimmy Carter shook author Victor Lasky's hand and said it was an honor to have him as a guest in the White House. But if the two men meet again, the president may not be so gracious. The reason: Lasky, whose last bestseller was a defense of Richard Nixon called It Didn't Start With Watergate , is taking on Carter.

"A lot of dirty tricks went into Mr. Carter's rise to power," asserts Lasky, whose forthcoming book title has a familiar ring. It's called Jimmy Carter: The Man & the Myth , which hearkens to Lasky's first big seller, JFK: The Man & the Myth . Critics accuse Lasky of writing books by weaving together news clips that support his conservative politics.

But Lasky says for this project (due out in May from Richard Marek), he trekked around Georgia "talking to people who knew Mr. Carter in the old days... It's going to surprise a lot of people in Georgia -- that's all I'm going to say."

Lasky says he will paint a picture of an "uptight" presidential campaign in which every move was orchestrated to such a degree that a Carter media adviser worried about the candidate's 5-foot, 9-inch height.

"before the debates at the Walnut Street Theater in Philadelphia," Lasky says, "Barry Jagoda went to the Ford people and said Ford had to stand in a depression, a little hole in the stage, or Carter would have to be given what a friend calls a 'man-maker,' a small box to stand on. So they'd both be the same height."

Lasky also says he will resurrect some little-noticed stories about the Carter campaign, including the one Richard Reeves included in his book, Convention . According to Reeves, the Carter camp had a trailer filled with sophisticated electronic equipment that provided the capability of monitoring all radio communications on the convention floor. Lasky suggests revelation of the trailer's activities bofore the election could have affected the outcome. How did he miss doing a book on Gerald Ford?

Laughs Lasky: "He wasn't there long enough."