Several times a day, a head-turning commotion brings everyone to a halt in the marble fifth-floor hallway of the District Building.

A wiry, balding, impeccably dressed little man bursts from an office at one end of the hall. He is difficult to avoid and impossible to ignore, and the activity around him suddenly fills the corridor. He flails his arms to emphasize some point, glances down to scan documents thrust in front of his face and booms orders to the three or four aides who have followed him part of the way, but now peel off and return to home base.

City Administrator Elijah B. Rogers is on his way from his own office to Mayor Marion Barry's. The city's Home Rule Charter says that the mayor, at the eastern end of that marble corridor, runs the local government. But that's not true -- at least, not recently.

Rogers, at the western end, does.

In what some city officials see as the further maturing of the District of Columbia's fledgling home rule government, and what others see as a product of the skills of a veteran bureaucratic infighter, Rogers has consolidated unprecedented power in the office of the city administrator.

"I'm the first so-called professional city manager in Washington, so I think we probably approach the job differently" from the way Julian Dugas handled the post under former Mayor Walter E. Washington, Rogers said in a recent interview. "In terms of sheer personality, drive and intensity, I think we have made a difference."

Actually, there were two professional managers earlier in Mayor Washington's tenure, but that was before home rule -- back in the days when the D.C. government was much more like a federal agency. The responsibilities of local officials, and the power they wield, have since expanded rapidly.

"The function of the mayor is to be out working with citizens, seeing what kind of city we ought to have," Rogers said. "The city administrator runs the city day to day."

But Rogers has assumed another function: He acts as a lightning rod, deflecting criticism from Barry, who is widely expected to seek another term.

For example, when the U.S. Attorney's office here began a criminal investigation of two officials in the city's licensing agency earlier this year, all inquiries were routed to Rogers. Barry declined to comment on the potentially embarrassing episode, which involved one of his major appointees, on the grounds that it was an "operational" matter, not a "policy" matter requiring a statement from the mayor.

"It's an evolving process. I've learned more about how to deal with the press," Barry said yesterday. "We've just become more sophisticated. I started out speaking for this government on things I might not have been informed about, that I didn't have personal and daily responsibility for."

But Barry's use of this new system, in which department heads, and ultimately Rogers, comment on day-to-day matters, is selective: Last year when the city's infant mortality rate went down, Barry made the announcement. This year, when the rate went up, reporters were told that Rogers was the highest-ranking official who would comment.

A District Building insider, an official who asked not to be named, had a simple explanation for Rogers' ascendancy: "He is the best politician in the city government."

But that same source said Rogers' political acumen is largely internal, and added that in his opinion, Rogers is "still learning" how to gauge the external political impact of District Building actions.

An example cited by the official is the hard line Rogers and his budget officers have taken toward the school board, using every lever to force the board to conform to budget procedures instituted by Rogers, without realizing that many potential voters have begun to feel that the Barry administration is slighting the schools by unnecessarily withholding needed funds.

Rogers' emergence has coincided with the virtual disappearance from the city government's day-to-day management of the other erstwhile member of the ruling triumvirate, Ivanhoe Donaldson, Barry's general assistant and chief political aide.

Donaldson once routinely performed government-wide administrative functions, such as his role as head of a task force designed to improve the city's cash management last year. He is now sequestered across town, blocks away from the cauldron of activity at the District Building, as acting head of the Department of Employment Services.

Despite rumors of friction between Rogers and Donaldson over status as the No. 2 man in the government, Donaldson still talks by phone to the mayor almost every day and continues his role as the mayor's primary political advisor. In fact, both men perform political roles for Barry, who said yesterday that he is "moving closer and closer to a positive decision" to run again next year.

Donaldson -- along with another Barry political aide, Matthew F. Shannon -- is in charge of the city's youth summer jobs program, which is viewed as crucial to Barry's reelection strategy of laying to rest nagging questions about his ability to manage the city in a professional manner. The annual jobs program, an issue in Barry's successful 1978 campaign, was botched the first two summers of his administration, but has not been criticized as much this year.

"Ivanhoe is very much tied down with the summer jobs program," a department head said. "The mayor regards that as a very, very sensitive thing to him. He decided that Ivanhoe could give it the kind of attention that was needed -- knowing the kind of political impact it could have if the thing were a mess. The mayor saw it in safe hands by having it in the hands of Ivanhoe."

Rogers, whose powers are delegated by the mayor, is now an official link in the chain of command: Barry sent an order to all his department heads several months ago spelling out the fact that they were to report to Rogers -- the clear implication being that end-runs directly to the mayor's office would no longer be allowed. Once, under former mayor Washington, the department heads enjoyed a measure of autonomy; now, it is clear who's boss.

Throughout much of any given day, at least one department head is waiting in Rogers' outer office for an audience: William B. Johnson of the Department of Environmental Services, bringing more ideas on the city's pressing sludge disposal problem. James E. Buford of Human Services, with a status report on efforts to regain accreditation at the city's troubled facilities for the mentally retarded and the elderly. Robert Moore of Housing and Community Development, with problems concerning public housing rehabilitation. Lawrence P. Schumake III of Business and Economic Development, with a task force report on cable television.

Department heads, who must deal with Rogers constantly, are reluctant to discuss his new role on the record. But with the understanding that their names will not be used, they describe a dramatic shift in the way the city government operates, with the 41-year-old Rogers as catalyst and chief beneficiary of the change.

"What we are moving towards is a city manager form of local government," said one agency head who had several clashes with Rogers and complained about him to the mayor but was finally rebuffed. Now he says he is of no mind to publicly challenge the system. "In other cities, the mayor has the final responsibility and the department heads answer to him. The mayor is elected, and so the department heads are accessible to the voters. Who elected Elijah Rogers?

"He clearly feels that all the decisions are his and the mayor's, that everyone else is just a kind of unit supervisor," the agency head said. "Is that good? I don't know. One of the congressional committees overseeing D.C. affairs has already said that too much power may be going to the mayor under home rule. Well, the mayor has delegated all that power to Rogers."

"Elijah is clearly the day-to-day manager of the city," Donaldson said. "He's excellent -- a crackerjack manager. When he says no, it's no. You don't find department heads going around Elijah any more to the mayor to try to get something done."

Rogers' political role is different from that of Donaldson: In addition to deflecting criticism, he is supposed to see to it that the administrative initiatives Barry wants implemented are done right -- like the city's current ambitious street repair program, the series of planned or ongoing improvements in public housing that Barry has been trumpeting in weekly announcements or changes that make it easier to apply for and collect unemployment benefits.

According to department heads, Rogers also red-flags items from the agencies that might have political impact and brings them to Barry's attention, particularly budget-related items that could have a negative impact on services.

Rogers acknowledged in an interview that he has sought to expand the city administrator's job and believes he has succeeded, though he points out that the ultimate power remains Barry's. "The mayor delegates, and if he delegates he can take away," he said.

Rogers is small and trim, a bit over five feet, with a booming voice that should belong to a larger man. At work, he is always immaculately dressed -- almost invariably a three-piece suit and a long-sleeved shirt with French cuffs monogrammed "Baby," his middle name. He zips around town in a silver Alfa Romeo convertible with D.C. license tag No. 3.

In his large, neat office, Rogers keeps a small refrigerator with a supply of Miller beer. He begins to sip a can late in the afternoon when the building has emptied, and he is left with the cleaning crews and the night security officers.

"Part of it is that after I've been working with the mayor for a couple of years, the chemistry begins to click," Rogers said in explanation of his expanded role. "You get to know each other -- we're definitely friends. Part of it is knowing where the mayor stands on various things. I probably know where the mayor is on 99 percent of the things that come up. Obviously, we've grown much closer."

Rogers has declined an offer to return to the job he had before coming to Washington, as city manager of Berkeley, Calif., and is now one of eight finalists being considered for the job of city manager of Dallas. The job in Dallas now pays $92,000 a year, versus Rogers' current $53,000. The fact that he makes less than some other municipal managers around the country is reportedly a sore point with him, although he declined to talk about it for the record.

Although he said he will consider other offers, he added that he likes his job and is not seeking another one. The D.C. government, he frequently says, has city, county and state functions that are unique in America.

"I have more responsibility here, more authority," Rogers says with a wide grin, "than any other city manager in the country."