The Mayor’s Challenge . . .

What might have been a mean and divisive mayor’s race in the city of Los Angeles has melted down to virtually no race at all. City Councilman Zev Yaroslavsky, looking at a series of polls that gave him no chance to beat Mayor Tom Bradley, wisely withdrew.

There is an irony here. The fact that an un- precedented fifth term may come easily means that Bradley must bear down harder on the challenges of the city as he works toward what will by 1993 be 20 years as the chief executive of one of the world’s great, throbbing and thriving cities.

Bradley may still have challengers, but they are not likely to be politicians of stature who could give him a battle on the issues. Candidates do not carve out successful careers by starting campaigns from scratch with just three months to get their messages across.

Yaroslavsky was deterred in large part by a sense of vigor at City Hall that was little in evidence during most of Bradley’s fourth term. A year ago it seemed safe for a potential challenger to assume that at age 71, often seeming weary of coping with the problems of Los Angeles, Bradley would be a soft target.

The new sense of energy is ultimately due to Bradley himself. But it is also in part the doing of Deputy Mayor Mike Gage, a rare combination of skillful urban politician and dedicated environmentalist who helped put the office at a higher level of alert and make the mayor more visible.

It worked politically. Now the team must make it work in substance--with better management of growth, more creative assaults on drugs, gangs and other engines of crime, with new approaches to transportation and to keeping the region’s air clean.

That will require a different style than Bradley has displayed so far in his years at City Hall, where he was more a healing presence than a manager, not so much directing energies as calming emotions in the most ethnically diverse city in the nation. That style has its uses, but in the process the civic job jar has filled to overflowing. There can be no substitute during the next four years for focusing City Hall’s new sense of vigor directly on the major problems of Los Angeles.