If she is elected mayor Tuesday, Democratic nominee Sharon Pratt Dixon says, she will fire 2,000 mid- and upper-level managers to reduce the size of the D.C. government payroll.

But Dixon says she can't say for certain yet which workers and agencies will be cut; she first must order a management audit.

The audit, by an outside consulting firm, would serve as a blueprint for her efforts to trim the bureaucracy and close the city's projected $100 million budget deficit, she said.

"It has got to be seen that I'm really going after people who really haven't produced," Dixon said of her promise to fire city workers. "Those are the ones we isolate. Those are the ones we get rid of."

Dixon is borrowing a page from the corporate textbooks upon which she relied as an executive of Potomac Electric Power Co. In regulated companies such as Pepco, "management audits" by outsiders have long been used to ensure that operations are as lean and efficient as possible.

Other U.S. companies, facing increasing competitive pressure from Japanese and Western European firms, have also made use of such analyses in recent years, frequently calling on firms such as Booz-Allen & Hamilton and McKinsey & Co. to recommend ways of cutting overhead and streamlining operations.

"Everyone in the private sector has really learned to manage more efficiently in the last 10 years," said Richard W. Winger, a partner at the Boston Consulting Group. "City government has yet to catch up."

Dixon, who has repeatedly criticized the D.C. government as bloated and inefficient, said she would hire an outside firm through a competitive bidding process and set it to work on combing through the 48,000-member government almost as soon as she takes office in January.

GOP nominee Maurice T. Turner Jr. has also called for an audit of D.C. operations, although he has not made it the kind of central campaign theme that Dixon has.

The idea for an audit was first suggested two years ago by D.C. Council Chairman David A. Clarke and was picked up during the Democratic mayoral primary campaign by Dixon, Del. Walter E. Fauntroy and council member Charlene Drew Jarvis (D-Ward 4).

As Dixon explained it, the auditors would review the operations of "every office and agency of the city" -- probably starting with the Human Service and Public Works departments -- by interviewing managers, front-line workers and, in some cases, the consumers of the government service in question.

The auditors would then report back within three months with at least preliminary recommendations for eliminating duplicative positions, identifying unproductive employees and determining other ways of streamlining government, Dixon said.

Dixon said she is unsure about the cost of her proposed audit. Some outside consultants say she may also be overly optimistic about the speed with which such a review could be carried out. Private sector management audits of much smaller bureaucracies can take six months to a year or longer to complete.

Anyone auditing the D.C. government must also contend with unions, civil service regulations and other features of city bureaucracy that make reducing overhead more complicated than in the private sector.

In a recent interview with The Washington Post, City Administrator Carol B. Thompson questioned whether Dixon would have the luxury of time to carry out a comprehensive audit. Within a month of taking office, the new mayor would have to send a proposed 1992 budget to the D.C. Council, one that closes the huge budget deficit facing the city.

"I don't think you have time to stop or hold while you do an audit," Thompson said. "You're going to have to come in day one and keep moving."

But several outside management consultants said city government is ripe for the same kinds of improved management techniques that have helped private industry.

Some said Dixon, in fact, may be on the low side in her estimate of how many workers can be cut from the bureaucracy without sacrificing service. Winger said good audits can help private sector organizations reduce overhead and personnel by 20 to 40 percent.

"Unfortunately, {the late Chicago} Mayor {Richard J.} Daley is not the only one who ever built a bureaucracy on patronage," said William J. Edwards, of the Arthur D. Little Co., a research and consulting firm in Cambridge, Mass. "But the process can be altered, and the process can be better. If the people are committed to it, it is doable."