If reason ruled in politics, the Democratic party would urge its presidential candidates to eliminate the vitriolic posturing from their campaign, and would then begin to concentrate on the only question that matters: Who can beat Reagan? That is different from asking whether Walter Mondale would make a better chief executive than Gary Hart, or whether Hart’s “new ideas” are preferable to Mondale’s old-line liberal values.

What troubles me is that, given the rising nastiness, this campaign begins more and more to resemble the terrible script written in 1972, when another new face, George McGovern, was buried by Richard Nixon’s landslide. That year, as McGovern drove toward the nomination, some of the old, regular elements of the party — ranging from Mondale’s liberal mentor, Senator Hubert Humphrey, to the AFL-CIO’s George Meany — resorted to withering personal attacks that destroyed McGovern’s chances for election.

Now, Mondale and the AFL-CIO’s Lane Kirkland are attempting to do the same thing to Gary Hart. Organized labor is caught in its own crisis of impotence. Having endorsed Mondale, the unions are now desperate to prove that they can actually deliver for him. If they don’t, they will stand naked in the political arena. That fear has led Kirkland and other labor leaders to savage Hart, though he has a perfectly honorable record of support for blue-collar issues. If they succeed, they must share the blame for a second Reagan term.

There are actual and substantial differences between Hart and Mondale, but they have been magnified and distorted beyond reason by the campaign. The real choice should be which one has the best shot at dislodging the Gipper from the White House. In my view, Gary Hart would be a more promising challenger, capable of mobilizing a broad coalition of voters discontented with the Reagan administration. Walter Mondale looks, more and more, like the voice of yesterday, unable to inspire and unwilling to articulate a fresh perspective on the future.

This disagreement over who can beat Reagan is the core of the Democratic party’s dilemma in the spring of 1984. Some analysts think the contest is already over, that neither of the leading Democratic contenders has a prayer in November unless the president stumbles into a foreign crisis or an unforeseen economic disaster — something that would abruptly dissipate the aura of good feeling generated by the economic recovery. Even then, Reagan might benefit in the short run. People usually rally around a president when he’s confronted by crisis — like hostages in Iran or Soviet missiles in Cuba — and Reagan is adept at stimulating that impulse.

Even the ominous rumblings in Central America might be good for the Gipper, so long as the public does not grasp the full implications of his bellicose policy there. But my own hunch is that many Americans are now wise to this game, and fear of what Ronald Reagan might do in Central America and elsewhere is one of the Democrats’ most potent issues.

For that reason and many others, most political analysts predict that 1984 won’t produce a Reagan landslide but a close election that could go either way. Too many Americans dread the prospect of a second Reagan term and its potential for creating foreign conflicts and deepening the injury and injustice of his domestic policies. About forty to forty-five percent of the American public have seen through Reagan’s smile and are committed to voting against him this fall. To win, the Democrats must convince another five or ten percent.

Even though no one envisions him as the party’s ultimate nominee, it is Jesse Jackson — not Hart or Mondale — who has done the most to improve Democratic prospects in that regard. The extraordinary surge of newly activated black voters whom Jackson has drawn into the primaries promises to alter the electoral landscape for many years to come. If Mondale or Hart become president, he can thank the charisma of Jesse Jackson.

Consider these examples: The black turnout in the Georgia and Alabama primaries increased by more than 100 percent this year. For the first time in history, black Georgians actually voted at a higher rate than whites did. In Illinois, depending on how turnout is measured, blacks increased their voting by fifty-four to seventy-five percent. In New York, Jackson had a similar impact.

Opinion surveys have turned up an unprecedented trend this year — black voters, who traditionally have been the most alienated from the political process, are now paying more attention to the election than whites are. An ABC-TV poll found, for instance, that among likely voters in New York, forty-six percent of blacks were following campaign events closely, compared to only twenty-eight percent of whites.

Among people who said they were certain to vote, eighty-three percent of blacks had watched at least one of the candidates’ TV debates, compared to sixty percent of whites. If, through this new interest in politics, blacks can be persuaded to remain in the Democratic fold and support a white candidate against Reagan, then the electoral map of Ronald Reagan’s 1980 landslide will be torn up.

Obviously, in order to capitalize on this groundswell in the fall, the Democrats have to nominate a candidate who has Jackson’s blessing and full support. But the nominee must also be able to mobilize all of the other elements of an anti-Reagan coalition. And is that Hart or Mondale? Each has his own assets and liabilities. That’s why the choice is such a tough one.

Peter Hart, who does Walter Mondale’s polling, is as cautious and undogmatic as his candidate. When he makes the argument for Mondale’s advantages, he is careful not to claim that Gary Hart would necessarily lose to Reagan, only that Mondale would run stronger.

Pollster Patrick Caddell, now a key adviser to Gary Hart, is less generous. Mondale is a sure loser, he thinks.

First, the Mondale argument:

“The case I’ve been making since last summer,” said Peter Hart, “is that a Democratic victory in ’84 will depend on expanding the electorate. We had a turnout of fifty-three or fifty-four percent in 1980. My theory — and the primaries bear this out — is that this year the turnout will be larger. We could get it up to fifty-seven to fifty-eight percent, and that changes everything, because most of the new voters will be Democrats. The increased turnout comes from core Democratic groups, and Walter Mondale has the ability to stimulate those groups. Whether it’s blacks or labor families or ethnics, Walter Mondale is their person.”

In normal times, such voters are the main components of the Democratic coalition. One reason Reagan won in 1980 was his ability to pull away a significant slice of blue-collar voters whom Democrats count on. Mondale looks like the stronger contender to some analysts because his natural base of support, going back for many years, is with those groups. Gary Hart’s biggest handicap is that these voters simply don’t know him very well.

Could Hart overcome that unfamiliarity as the party’s nominee? A lot depends on how durable his public image proves to be in the coming weeks. The danger is that once the glitter of newness fades away, Gary Hart won’t be able to claim a solid base among traditional Democratic voters, and with a few missteps in his campaign, he could plummet rapidly in public esteem. Even Hart’s own counselors admit that possibility.

But the choice of staying with Mondale because he is tried and true looks more and more like a decision to stick with damaged goods, rather than take a worthwhile risk that holds the possibility of victory. Mondale may win the nomination and discover in the fall that he has no appeal to the voters outside those regular Democratic groups. If that’s true, then Mondale may have a very difficult time defeating Reagan.

Despite his overwhelming early advantage and his primary victories, Mondale has been declining in public esteem since the first primaries. In polls that ask voters whether they have a favorable or unfavorable overall view of a candidate, Mondale’s “unfavorable” rating has been steadily going up — thirty-one percent in February and forty percent in late March, according to a CBS-New York Times survey. Peter Hart acknowledges this troubling trend, but he insists it will be quickly reversed once Mondale is the party nominee.

More crucial than Mondale’s presumed advantages with traditional Democrats, Caddell believes, is Gary Hart’s appeal to new and younger voters, to independents and even to Republicans who loathe Reagan but probably couldn’t bring themselves to vote for an old-style liberal like Mondale. In raw numbers, of course, the young and independent voters are not nearly as substantial a group as are labor families or blacks in the Democratic equation. But they are vital nonetheless, because close elections are won on the margins — the extra voters a candidate can pull into the regular coalition. If Mondale is the nominee, the polls suggest many of these voters will feel more comfortable with Reagan’s brand of optimism. More likely, many others will simply stay home, disgusted with the choice.

“The basic democratic constituencies are going to turn out and vote against Reagan, no matter what,” Caddell argues. “The question is, where do we get the rest of the votes? Reagan is very good at setting the agenda and controlling the debate, and the only way to beat him is to have a candidate who can make the issue the one thing Reagan can’t deal with — namely, his age. He’s a seventy-three-year-old president with no stake in the future, and that will become very clear if Gary Hart is the candidate against him. That’s why the White House has always wanted to run against Walter Mondale: because then, Reagan can run against the past.”

Many voters in their twenties and thirties are getting serious about presidential politics for the first time and have no partisan attachments. Hart’s success at mobilizing these younger voters could be as significant for the future of the Democratic party as Jackson’s ability to enlarge the black electorate. More likely, these voters will remain independent, bouncing back and forth, depending on the candidates and issues. In 1984, however, they are up for grabs — they like Gary Hart, but if the Democratic nominee is Mondale, many are likely to stick with the Gipper.

All in all, I think Caddell has the best argument. As the nominee, Hart would have some difficulty activating those core groups that don’t know him well or that mistrust him. But his voting record as a senator attests to his basic loyalty to those groups, from the poor to organized labor, Jews and blacks. “Gary Hart is not known among black voters,” said Dotty Lynch, the candidate’s pollster. “But he has an impeccable civil-rights record, and I expect, as they get to know him better, blacks will vote for him enthusiastically, if he’s running against Ronald Reagan.”

In politics, of course, the combatants use whatever weapons are available to them. Thus, the Mondale campaign attacks Hart’s character — the unknown young man who changed his name versus the experienced former vice-president — while Hart tries to focus on real issues, like U.S. military involvement in Central America and Mondale’s failure to take a stand on Vietnam.

Gary Hart has the high ground on this subject, and Mondale’s responses are not reassuring. But there is a danger for Hart, too — the lessons of Vietnam have never been fully learned by the Democratic party or the American public. This is a powerfully polarizing issue that could tear the Democratic party apart in 1984, as it did in 1968 and 1972. If the aging cold warriors successfully portray Hart as an irresponsible peacenik, then Mondale may win the nomination. But it won’t be worth much. Reagan will be the real winner.

Should the Acrimony Between Hart and Mondale continue to deepen, and if neither amasses a clear majority of delegates by the time the Democratic party convenes in San Francisco, we will see, for the first time in a generation, a convention where the delegates really will choose the nominee.

Political thrill-seekers are already promoting various scenarios in which Teddy Kennedy, or New York governor Mario Cuomo, or Arkansas senator Dale Bumpers, or any one of three or four other “new” new faces becomes the nominee. Kennedy has already issued an unequivocal disavowal. The others might make appealing nominees, but I think the speculation about brokered conventions and dark horses is really a way to duck the essential question: Who can beat Reagan?

Gary Hart brings a certain risk to the equation. But on the whole, that’s an asset more than a liability. He promises to be different from the past, and that is something voters of all stripes are yearning for. He offers an alternative to the coldwar ideology that led us into Vietnam, and to the undisciplined fiscal policies of past Democratic regimes, just as he stands to move us away from the brutal class-interest politics and runaway nucleararms race promoted by the present administration.

Yes, Gary Hart is a bit fuzzy on some things and is personally untested. Yes, he has some puzzling corners to his personality, and he does sometimes seem offensively self-confident. These qualities tend to irritate established party authorities. But people forget that organized labor and liberal stalwarts had similar suspicions and uneasiness about John F. Kennedy when he became the party’s nominee in 1960.

I am not suggesting that Gary Hart is another Kennedy. But I do believe that his candidacy embodies some of the same political risks and opportunities for the Democratic party. Given all the unknowns, Hart just might win. If the Democratic party cannot take a deep breath and embrace risk, then it really has lost its soul and deserves whatever fate the voters have in store.