Found this gem from 1998 thanks to a regular on DailyKos:

The fact that McCain had made the tasteless joke was reported in major newspapers, as was the vain attempt by his press secretary to initially deny what McCain had done. But in several major newspapers, the joke itself was kept a secret. When McCain subsequently apologized to President Clinton, the Washington Post, in its personality section, noted the apology but said the joke "was too vicious to print."

The Los Angeles Times, in its Life & Style section, provided an oblique rendering of the joke that did not fully convey its ugliness. When Maureen Dowd penned a column in the New York Times about the joke, she wrote that McCain "is so revered by the press that his disgusting jape was largely nudged under the rug." But Dowd chose not to relay the joke, either.

The joke did appear in McCain's hometown paper, the Arizona Republic, and the Associated Press did report the joke in full, so everyone in the press had access to McCain's words. But by censoring themselves, the Post, the Times and others helped McCain deflect flak and preserved his status as a Republican presidential contender.

Salon feels its readers deserve the unadulterated truth. Though no tape of McCain's quip has yet emerged, this is what he reportedly said:

"Why is Chelsea Clinton so ugly?
Because her father is Janet Reno."

The joke may be crude, but it pales in comparison with the published details surrounding the presidential sex scandal. McCain's two-liner conveys some interesting insights into what he considers humorous (lesbianism, a young woman's physical appearance), particularly since it was delivered to a Republican crowd. Remember, this is the party that champions pro-family values.

McCain's lapse in judgment -- admittedly, not as big a lapse as having a sexual relationship with an intern -- may be a significant clue into aspects of his "character," and thus relevant to the voting public. But many voters have been spared this insight, thanks to the censors in the press.

The joke was funny IMO, but hardly presidential material. Also, hardly surprising coming from John McCain.