Now that Gary Hart has thrown his small clothes back into the ring, the question that has to be answered is just how seriously the American people will take his hanky-panky with Miami model Donna Rice. Put a trifle more harshly, will they vote for a presidential candidate who can't manage a mild case of adultery?

Hart's reentry into the Democratic presidential race is stunning and unprecedented in modern times, and there are very good reasons for that. Politicians aren't notorious for having a keen sense of when they should pack it in -- which is why they pay advisers to give them the bad news. Hart -- who says he has no staff -- says he has been listening to his family, particularly to his children who never wanted him out of the race. Hart's not listening to the pros, he is listening to himself -- proving once again that the human animal is capable of rationalizing just about anything if he sits around long enough and thinks about it.

The experts are saying Hart is going to run as the consummate outsider, and the meaning of that may take on a whole new dimension when he sits down on Jan. 15 with the six other Democratic contenders at the next presidential primary debate.

The immediate reaction in the polls to his bombshell announcement was both mixed and erratic: A USA TODAY/CNN poll showed that more than 40 percent of those queried thought he should run. Nearly 30 percent of the Democrats polled said he was still their first choice for the nomination. An ABC poll taken Tuesday night showed that a staggering 49 percent of Americans view him unfavorably, and four in 10 would not vote for him under any circumstances. On the other hand, he immediately regained his spot as the Democratic front-runner, with 28 percent of the Democrats polled saying he is their first choice as compared to 22 percent who would choose Jesse Jackson.

Hart's instant reentry at the top of the charts is a tribute to the power of publicity -- not the power of ideas -- and to the enormous media splash he made with his announcement. He may be planning a campaign on the issues, but so far he's winning on name recognition. The only other Democratic candidate who is anywhere near as famous is Jesse Jackson.

The night of his announcement, Hart was able to capture nearly an hour of time on ABC's "Nightline." Ted Koppel asked how he intended to handle questions about his personal life. Hart responded, in part: "I'm not naive; they'll be some very bad stories, and who knows what's going to be written and said. It can't be an awful lot worse than what's already been said, but there is no way in the world I intend to respond to that because it doesn't matter."

And later on: "I made a mistake. I have paid for it dearly this year . . . . If there are those in this country who wish to hang me for that, I suppose they'll continue to do it. But they better be prepared to hang an awful lot of other people in public life."

Moments earlier, Hart had attempted to portray himself as the soul of discretion by noting that it had required "surreptitious surveillance to find out the possibility that I might be involved with someone else." This from a man running for the presidency, who challenges the press to follow him, and then proceeds to take a comely yachting companion to his house for the night while his wife is out of town. That's not discretion. That's folly.

Lots of presidents -- and lots of other people -- have committed adultery. Hart is right on one thing, which is that the break-even point in these matters is whether the person, particularly someone running for president, does it quietly and sensibly or whether he does it blatantly and foolishly. Call that hypocritical if you will, but hypocrisy has its utility.

The president is expected to have poise, to be discreet, to be a person who can keep secrets and provide moral leadership. He's got to be able to stand up to the Kremlin without having a phalanx of arms control negotiators sniggering in their vodka.

Hart's conduct has become open and notorious. It is impossible to ignore. Rumors about his womanizing have become public admissions -- and there is nothing in the record to suggest that he intends to change.

He says he wants to take his campaign directly to the people. If he is not being just terribly cynical, if he really thinks he has a chance to be taken seriously, the real question facing Hart and ultimately the American people is where do they come down on extramarital activities.

We certainly wouldn't want a president who might start a nuclear holocaust by knocking the red telephone off the bedside table during an indiscretion.