In the vernacular of the executive staff of Gov. Harry Hughes, it is known as "going to lunch with Johnny."

The phrase describes the way senior administration officials who have fallen from grace are fired, and reflects the power of the man who picks up the check and wields the ax: Hughes' chief of staff and alter ego, Ejner J. (Johnny) Johnson.

Over the years, some of Maryland's most politically entrenched officials have -- literally or figuratively -- gone to lunch with Johnny. One was Personnel Secretary Theodore Thornton, the only black in Hughes' original cabinet, whose politically delicate dismissal was carried out by Johnson. Another was Insurance Commissioner Ed Birrane, whose departure from state government Johnson negotiated in a car parked on State Circle -- as an unsuspecting capital correspondent for the Associated Press sat on the hood waiting out a State House fire drill.

Johnson, a 53-year-old former journalist and veteran state bureaucrat, joined the governor's inner circle 6 1/2 years ago. He has flourished under a chief executive who delegates considerable authority, becoming the dominant figure on Hughes' staff and at times almost a surrogate governor.

From decisions on the state's $8 billion budget, to personnel moves, to mediating disputes between agency heads, to management of the most pressing crises including current problems in the savings and loan industry, Johnson always seems to play a pivotal role.

"I like him, I'm comfortable with him, and I have the utmost confidence in him," said Hughes. Given the governor's penchant for understatement, the description is a ringing endorsement.

Johnson's dominance, say some observers, reflects a relative weakness of the rest of the staff and of the cabinet, a basic flaw in the Hughes administration.

In normal times, this final year of Hughes' governorship would probably have been the apex of Johnson's career. But there are subtle signs that Johnson's position in state government, like his boss' ambition to become a U.S. senator, may have been undermined by the debacle in the thrift industry that began last spring with depositor runs on several large thrifts.

Associates of the governor deny that Johnson's clout is on the wane -- the evidence, they say, is that Hughes wants Johnson to run his Senate campaign. But some veteran State House watchers suggest that even if Johnson is given a principal role in the campaign, he is still being eased out of the arena where the real power lies, the epicenter of state government that Johnson spent a lifetime training for.

Though Hughes describes his chief of staff as "a good first sergeant," many who have watched Johnson operate over the years give him a more exalted rank.

State Del. Timothy F. Maloney (D-Prince George's) has a photo of Johnson hanging above his desk in his legislative office, taken when Johnson was commissioner of motor vehicles during the 1970s. Why that photo in a spot where others might hang a picture of Hughes?

"Because he's the real governor," jokes Maloney.

Johnson commands almost unlimited access to the governor and a loyal cadre of middle managers sprinkled throughout state government. As a result, he has outlasted or outmaneuvered his few rivals on the executive staff and in the cabinet.

Within a few weeks of joining the staff in the fall of 1979, Johnson established his presence by evicting Secretary of State Fred Wineland from his corner office across the hall from the governor's.

A few months later, the Johnson style was parodied in the annual Legislative Follies.

In a skit entitled "Chief of Staff," Johnson -- portrayed by a state senator wearing a German military helmet -- barked orders at Hughes and his staff and secretly plotted Hughes' political demise with then-Lt. Gov. Samuel Bogley, who Johnson promised to keep on when he became governor.

In a subsequent letter to two legislators who helped produce the Follies, Johnson poked fun at "mein Prussian approach" to government. "I vould suggest," wrote Johnson, "you talk to zum of ze staff members here to verify my easygoing nature; they will be available after reveille immediately upon completing the policing of ze State House grounds."

The skit and self-deprecating response illustrate two equally characteristic sides of Johnson, a Brooklyn native and son of a New York City policeman who took a leave of absence from his political reporting job on the old Baltimore News Post in 1961 to work for Democratic Gov. J. Millard Tawes -- and three governors later is still drawing a state paycheck.

Johnson's many admirers in state government view him as bright, genial, politically adroit, and hard-nosed, a man with a long institutional memory who is the perfect chief of staff for a low-key and contemplative governor.

"Harry did himself proud when he brought Johnny in," said Deputy Attorney General Dennis M. Sweeney. "You need people who can make decisions without being nervous nellies."

To his critics, few of whom will speak publicly, Johnson is a power aggrandizer who is overly combative and whose only real loyalty is to himself. Johnson's compulsive need to be involved in every major decision, they say, has caused a number of talented aides to leave the administration, and meant that some brewing problems, like savings and loans in 1984, don't get the attention they deserve.

Both the critics and admirers agree that Johnson is a workaholic and a survivor. After being a speechwriter for Tawes, he became deputy motor vehicle commissioner under Republican Gov. Spiro Agnew, head of that agency under Gov. Marvin Mandel, secretary of licensing and regulation for Hughes and finally, chief of staff.

As head of motor vehicles, Johnson thrived on the challenge of running what is historically perhaps the most political of all state agencies.

One key figure in the Mandel administration, who insisted on anonymity, also remembers Johnson trying to undermine Hughes by complaining to the governor's aides about Hughes' performance as transportation secretary. Johnson denies it.

There have been no such rumblings questioning Johnson's loyalty since 1979, when Hughes plucked him from the Department of Licensing and Regulation to take charge of a green executive staff.

Johnson's control over the staff now extends even to the summer softball team, where he aggressively anchors the infield at shortstop.

Besides softball, Johnson is a skiing enthusiast. He and his wife, Grace, have five grown children.

In the legislature, Johnson is regarded as a forceful decision-maker.

In early 1981, for example, personnel secretary Thornton tried to implement a new system of scoring tests given to state job candidates that would have resulted in four out of five jobs going to minority or female applicants. Two delegates protested to Johnson.

Within two days, Johnson had written the legislators informing them that he and Hughes had overruled Thornton.

"The thing about Johnny is he delivers," said Del. Maloney. "You call extension 3004 and say I have a problem and he calls you back the next day and says 'we're going to do a,b,c,d and e.' You may not always like it but you get an answer."

"Johnny is the ultimate pragmatist," adds Maloney. "I'd be hard pressed to say what Johnny's ideology is except he deeply believes the trains should run on time. Which is all right as long as he works for someone who does have an ideology."

If Johnson helped smooth relations with the legislature, he has also ruffled some feathers in the cabinet.

Strong-willed cabinet members like former budget secretary Thomas Schmidt -- who lost considerable budget control to Johnson -- and former transportation secretary Lowell K. Bridwell, had running battles with Johnson over turf and access to the governor.

"Johnny's problem and my problem was that we both were very strong in our opinions of what should be done," said Schmidt. "When you get two people who think they know everything and are coming up with different answers, then you have a problem."

The dangers of Johnson's style, say the critics, are illustrated by his handling of an October 1984 memo from Hughes adviser George Liebmann. That memo warned the governor that there were big problems in the savings and loan industry, including widespread "self-dealing" by some unnamed thrift owners, seven months before the first run began on Old Court Savings & Loan in Baltimore.

Johnson was involving himself in other problems at the time, including an investigation of the slaying of a Baltimore prison guard. So he routed the Liebmann memo through regular bureaucratic channels. When the head of the savings and loan division sent back a generally reassuring reply, Johnson probed no further.

Press disclosures of the memo last fall unleashed a barrage of criticism upon Hughes for his handling of the savings and loan crisis, criticism which has not let up as Hughes prepares his bid next fall for the U.S. Senate.

A number of people with close ties to the Hughes administration suggest privately that Johnson should have accepted responsibility for not aggressively pursuing Liebmann's warning and resigned. Friends of the governor, who Hughes will not name, even recommended that he dismiss Johnson in order to siphon off some of the political heat.

"I said absolutely not," said Hughes.

Johnson, while arguing that more aggressive action on the Liebmann memo might only have provoked the inevitable crisis a bit earlier, nonetheless admits he was "culpable in not addressing" it. "I don't make any excuses for it," said Johnson. "I wish I had it to do over again."

Despite the vote of confidence from Hughes, there are signals that Johnson's role on the executive staff has suffered some erosion.

During the first week of this year's legislative session, a critical period when the governor introduces his budget and makes his state of the state address, Johnson took a skiing vacation in Europe.

And in recent days, he has taken time off to organize campaign fundraising events for Hughes. Johnson is now considering Hughes' offer to run the campaign.

All those signs have led to speculation that "the ultimate survivor" may be going under, talk fueled by rumors that Johnson has fallen out of favor with Hughes' wife Patricia, who has considerable influence within the upper councils of the administration and her husband's campaign.

"I've heard the rumors and I don't think they're true," said William Boucher III, a Hughes intimate and political adviser. "There's been no diminution of his authority and of the governor's confidence in him. If anything, the tough times have made them closer."

Even if unfounded, the rumors that Johnson is losing his grip make the prank pulled last summer by his old sidekick on the executive staff, John F.X. O'Brien, more poignant than funny.

The phone call from O'Brien came as the Hughes administration was trying to dig its way out of the worst of the savings and loan crisis. "Johnny," said O'Brien, "the governor has asked me to take you to lunch."