The feud between late-night talk show host David Letterman and Alaska Governor Sarah Palin is no laughing matter. The latest Rasmussen Reports national telelphone survey finds that nearly two-thirds of American adults (64%) say it’s inappropriate for comedians like Letterman to joke about the children of public figures.

Men (26%) approve of jokes about children of public figures more than women (17%). While a quarter of all adults are accepting of this type of humor, 65% of those with children and 63% of those without children disapprove of it.

Letterman’s gag last week referred to Palin’s daughter being knocked up by New York Yankees baseball star Alex Rodriguez during the eighth inning of a game. Palin accused Letterman of targeting her 14-year-old daughter who actually attended the game. Letterman insisted he was referring to Palin’s 18-year-old-daughter, Bristol, whose teenage pregnancy was a talking point of the 2008 presidential election.

Nearly half of Americans (49%) have not followed stories about the Letterman-Palin spat closely, if at all. Fifty percent (50%) say they have been following the story somewhat or very closely.

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Prior to last night, Letterman only used more Palin punch lines to “apologize” for his remarks. The Rasmussen Reports survey, which was conducted before Letterman’s official apology on Monday night, finds that only 16% thought Letterman’s apology up until that time was sincere. A plurality (44%) disagreed, and 39% weren’t sure.

Republicans were more than twice as likely as Democrats to doubt the sincerity of Letterman's apology.

But with protests growing, including the establishment of a firedavidletterman.com website, the host of CBS' "The Late Show" finally admitted to viewers on Monday night that the joke was a lousy one and that he was sorry. He added that the joke really cannot be defended.

Even before that apology, 41% had a favorable opinion of Letterman, but this is a nine-point drop from a survey at the end of last month. Forty-nine percent (49%) now have an unfavorable opinion of the CBS late night host. Interestingly, two weeks ago, women had a slightly more favorable view of Letterman than men, but now that has been reversed.

Just 20% of Republicans and 35% of adults not affiliated with either major political party have a favorable opinion of Letterman, compared to 63% of Democrats.

Commentator Debra J. Saunders crticizes what she believes was an overreaction to Letterman's original joke and urges Palin "to stop milking her role as GOP martyr."

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