It seems but a few short years ago that Gary Hart's hopes of being president went south because of publicity about his relationship with a young lady. Not too many years before that, New York Gov. Nelson Rockefeller's ambitions for the presidency were seriously damaged because of a divorce.

But in terms of public tolerance for marital infidelities of elected public figures, real or perceived, these events were light-years ago.Today's voters clearly aren't concerned about the peccadilloes of politicians. What just a few decades ago would have been considered sensational, career-ending revelations are now shrugged off as private and immaterial. That was reinforced by the blase' reaction of New Yorkers to Mayor Rudy Giuliani's marital problems.

Polls disclosed that an overwhelming number of the state's voters weren't concerned about Giuliani's public confirmation of what had been an open secret at least among the New York press, that his marriage was in trouble. Nor were they apparently shocked by his wife's scathing announcement that it was because he was consistently unfaithful.

Whether the mayor will go ahead with his presumed plans to run vs. Hillary Rodham Clinton for the U.S. Senate won't be known for several days, but it is clear the decision is likely to be based on the fact that he must undergo treatment for prostate cancer and not whether his personal lifestyle has damaged his image.

That isn't to say that Giuliani's family problems, combined with his illness, won't be a major distraction. The mental stress is bound to make it difficult for him to concentrate as much as required to defeat the first lady.

For this reason alone, Giuliani is believed to be having serious doubts about the senatorial race. There is another factor. Giuliani has been showing signs for sometime of trying to find a convenient way out of running for a job he regards as ranking third behind his current post and governor in the New York political pecking order. He has said he doesn't really care about politics right now.

In fact, it seems obvious that Giuliani cared little about his image or the election when he talked warmly at a press conference about the new woman in his life. That seemed almost calculated to enrage his wife. If it was an intentional provocation, it worked. She stepped outside the mayor's mansion and let him have it.

Despite all the pyrotechnics, the John Zogby poll conducted immediately after revealed that only about 15 percent of the state's voters gave a hoot about all this.

Then, one has to wonder, why should anyone outside New York? Well, the obvious answer is that his opponent is Hillary Clinton, the only first lady to run for public office. Because of her, this campaign is nearly as high profile as the one for the presidency.

Most observers believe that Giuliani's travails have managed to do the one thing necessary for his opponent to have a real chance of winning. They have made him the issue instead of Hillary Clinton.

The changing voter attitudes toward marital infidelity is fascinating. For much of the past century, reporters shied away from writing about them, using job performance as the rule of thumb for determining the legitimacy of a story.

Then for a number of years, the press decided it could no longer justify this oversight. Suddenly, the public seems to be saying "enough" unless it can be shown that professional duties are suffering.

Lyndon Johnson once cracked that a politician he knew was so unlucky "that he couldn't have done worse if he had been caught in bed with a live man or a dead woman." It probably wouldn't make that much difference these days.

Dan K. Thomasson is former editor of the Scripps Howard News Service.