MERCIFULLY, Chicago's mayoral campaign has ended. The accounts of that campaign were ample cause for despair. But many lessons one might be inclined to draw from tonight's election results have more to do with one huge, complicated city than with national patterns of race relations or party politics. As Hamilton Jordan observes on the opposite page, the Chicago election is not a microcosm of black/white political relations nationally.

Both candidates, Republican Bernard Epton and Democrat Harold Washington, indulged in villainy: Mr. Epton with his ambiguously race-baiting slogan, "Before it's too late," and Rep. Washington with his narrowly racial "We want it all." Mr. Epton's record on race, however, has been outstanding as a liberal state legislator. And Rep. Washington has followed earlier divisive statements that emphasized disdain for deals with white power brokers with less visible efforts to garner white support and build an inclusive transition team. On balance, the two candidates aren't villains, but they did precious little to resist the mounting ugliness. Each sought to gain from it, and in the process proved himself no nobler than the grimy process.

A more attractive black candidate with a more conciliatory campaign style would obviously have done a better job of holding white Democratic voters. It may be true that most whites just aren't "ready," as they say. But the events in Chicago are not a good indicator of broad backlash. There are too many special circumstances: from Jane Byrne to Jesse Jackson, from the decaying Daley machine to the politicized police force.

Beyond Chicago, there are more and more signs of effective black political participation across the nation. Growing numbers of black candidates not only claim a solid base among black voters, but reach out to address a broad range of issues and compete with some success for white votes. That is the dominant pattern. The lesson from Chicago is that the impressive political strength blacks now can wield in many places should be nurtured, not squandered by flawed candidates and reckless campaign tactics.

It is already a clich,e to say that everyone has lost in Chicago, whatever the outcome of the vote. Only a miracle of successful leadership on the part of the new mayor can bind the wounds and make Chicago a winner. That would provide the most important lesson of all.