The Reagan administration's argument that America's cities can afford to shoulder a major share of the fiscal burden for deficit reduction and tax simplification didn't play well here at the 53rd annual meeting of the U.S. Conference of Mayors last week.

In surprisingly strong bipartisan unity, the mayors who attended -- mostly those from midsized cities -- urged rejection of President Reagan's plan to end the federal deduction for state and local taxes, eliminate tax exemptions for municipal bonds, halt general revenue sharing and reverse municipal affirmative action programs.

The mayors of New York, Los Angeles, Chicago, Philadelphia, Detroit, Houston, Baltimore, San Antonio, Atlanta, Pittsburgh and Boston -- all big-city Democrats, many of them liberal -- skipped the conference. In their absence, the spotlight fell primarily on those who run second-tier cities.

Their message, underscored in interviews, was that although "urban America" is not limited to the aging Northeast and Midwest, many concerns of the largest cities are shared by chief executives of cities like Charleston, S.C.; Galveston, Tex.; Colorado Springs; Salt Lake City, and Kokomo, Ind.

"We certainly disagree on a number of issues," said Kansas City Mayor Richard L. Berkley (R). "But when it comes to the ones that impact the urban concerns, we agree. The differences are a matter of degrees."

The mayors appear to resent implications that they are on Easy Street with bloated bureaucracies and bulging bank accounts.

"Windbag politics is on its way out," said San Francisco Mayor Dianne Feinstein (D), one of the few chief executives from a major city to attend. "City leaders are expected to manage and utilize the private sector . . . . The day of your handout is really over."

Mayors like Jan Coggeshall (D) of Galveston said they spend half their time trying to lure economic-development projects, often without the tools offered by the federal government in earlier years.

"Traditionally, the job was to pick up the garbage and deliver the water. Today that's changed," Coggeshall said, recalling that one businessman told her, "I want a salesman, not an accountant" for mayor. "The mayors have become super salesmen," Coggeshall said.

Because bigger bureaucracies and higher taxes can be a liability, mayors like Bob Martinez (R) of Tampa have turned to user fees, state revenues and a leaner city payroll to gain a competitive edge.

In 1979, Martinez said, 82 percent of his budget went for payroll and operating costs; now the figure is 56 percent. "I'm not labor-intensive; I'm letting technology drive the work instead of letting workers drive it," he said.

In the same period that he has trimmed the city payroll by 1,000 jobs, the local economy has produced 25,000 jobs, more than enough to provide private-sector employment for those no longer on the city work force, he said.

Martinez, a former Democrat who switched to the GOP in 1983 and is now running for governor, is quick to say that his state would benefit from the elimination of federal deduction for state and local taxes.

But he, like other Republican mayors caught between their party and their constituents' concerns, said he worried about the cities serving as "a selected entity, the main instrument to balance the budget."

Colorado Springs Mayor Bob Isaac (R) called the proposed elimination of deductibility "just basically unfair." Mayor Henry E. Kinney (R) of Albuquerque said the older Frost Belt cities deserve some deductibility because they have absorbed so many of the nation's problems.

Mayor John E. Mercer (R) of Sunnyvale, Calif., in the heart of the Silicon Valley, said his city doesn't "deserve a nickel of revenue sharing" and voted against conference resolutions urging continuation of that program and deductibility. But Mercer said that what disturbed him most was not the thrust of the resolutions passed by the Democratic-dominated conference but "the rhetoric that goes with them, taking unnecessary shots at the administration."

Mayor Stephen Daily (D) of Kokomo said he resented federal efforts to play cities off against one another, especially since many Sun Belt cities prospered with the help of federal aid recycled from the Rust Belt in its more prosperous times.

"My community has put out a great deal of money in taxes, and we haven't asked for much in return," Daily said. Yet, when Kokomo needs help, he said, "I find the mayor of some nice affluent community out West saying, 'Gee, maybe we don't need that.' I think it's very convenient for a lot of people to have the Northeast quadrant of the country to bite the bullet."

It wasn't always that way, some mayors recalled. Until the middle of the Carter administration, Washington seemed to be "in a proposing mode," as one mayor put it, differing with the mayors primarily on what formulas to use for attacking urban problems.

Now, says Charleston Mayor Joseph P. Riley Jr., it appears as if "they've just got the shade pulled down" at the White House, "bored with it, not willing to follow through."

Salt Lake City Mayor Ted Wilson (D) complained that urban America's Cabinet secretary, Housing and Urban Development chief Samuel R. Pierce Jr., has been "an extraordinarily weak advocate of the cities."

"I don't think that anybody expects that it will go back to the way things were," Riley said. "What they can hope is at least there will be a maintenance of a reasonable urban concern.

"It isn't like we're floundering. We know how to do it," Riley said. "It's just a shame to pull it away."