THE FIRST PHONE CALLS came the morning after Rep. Herbert E. Harris II (D-Va.) lost his seat in a narrow election defeat Nov. 4: Golly, Herb, callers said. That's a damn shame. A loss to the district and the country. You know, we could sure use a lawyer of your caliber. Let's have lunch and talk it over, hey?

A week later, Harris had fairly firm offers of lobbying work from a government employees union and the mass transit industry, two interest groups he had defended energetically during his days in Congress.

Harris prepared to step into one of Washington's dizziest revolving doors and emerge as a lobbyist. "Negligence work or divorce work is just not appealing to me," he told a reporter.

His transition will raise no eyebrows in the capital. Many members retired from service or cast off by their constituents find they can earn more, worry less and still inhale the heady fumes of politics by working on Congress rather than in it.

The gravitation of public officials into lobbying is nothing new, but two factors seem to have accelerated the revolving door.

One is that today's Congress, with its demanding year-round schedule and ethics rules, cuts a member off from home and outside business interests. An ex-member may find he has little reason to go home, and little to sell (at least for his accustomed salary) but his knowledge of Congress.

At the same time, businesses have steadily enlarged their Washington presence, responding to increasing government regulation, a dispersal of power in Congress and competition from public interest groups. That has expanded the demand for knowledgeable people to report on what the govenment is up to and attempt to influence it.

"A former U.S. congressman, no matter how capable, is worth more in Washington than anyplace else -- considerably more," said Dan H. Kuyendall, a former Tennessee Republican representative with a string of lobbying clients. "Even those members who go to law firms back home end up getting sent back to Washington."

The closing days of the 96th Congress were the occasion for a discreet mating dance between outgoing members and special interests. Though the change in administrations made Washington a tight job market, interviews with a sample of outgoing representatives and senators indicated that ex-members were still in demand.

Rep. Robert Duncan (D-Ore.), who lost his May primary, was promptly enlisted to open a Washington office for a hometown law firm. He said his duties will include some lobbying on transportation and natural resources, the issues that were the focus of his attention in Congress.

"It will be not dissimilar from what I've been doing here: going down to the White House and trying to educate them on the problems of the West," Duncan said. Except, he noted, it will pay better.

Rep. William H. Harsha (R-Ohio), retiring as the ranking Republican on the Public Works and Transportation Committee, plans to open a Washington consulting firm. He expects his clients to be truckers, airlines and other transportation interests.

Rep. Bob Eckhardt, a liberal Texas Democrat unseated Nov. 4, said he was in "serious" discussions with two law firms about jobs that would include legislative advice and some lobbying in addition to litigation.

On the other hand, Rep. Lionel Van Deerlin (D-Calif.), chairman of Commerce's communications subcommittee, declined invitations to talk over jobs in that field and decided instead to return to San Diego to teach and write.

Van Deerlin, a former journalist, said a lawyer who stays in Washington "has something to sell other than influence. What do I have? All I have is the fact I worked on legislation and access to my colleagues. I really think I can hold my head a little higher if I'm doing something else."

Retiring Rep. Charles A. Vanik (D-Ohio), chairman of the Ways and Means subcommittee on trade, said he had several offers to work as a trade consultant in Washington. He said he refused to discuss them before adjournment and that, in any case, he would not feel comfortable returning to Congress as a supplicant for special interests.

Former members who lobby assert that connections count for much less than popularly believed.

"People think, erroneously, the way you get something through Congress is to go up to your old pals and say, 'Hey, do this for me, will you?'," said former Rep. James G. O'Hara (D-Mich.), a partner in the lobbying law firm of Patton, Boggs and Blow. "I don't think in four years I've ever asked anyone for a favor."

"The secret is knowing how the system works, how to get your issue to one committee instead of another, how to see that it gets acted on first instead of second, how to see that the amendments you don't want are nongermane and the amendments you do want are germane," he added.

"A very, very small percentage of your work is really dealing with members," said former Sen. Robert Taft Jr. (R-Ohio), whose clients include the American Hospital Association, Family Leisure Centers, Grocery Manufacturers of America, Hanna-Barbera Productions and Penn Central Corp. "You deal mostly with staff, and most of them I did not know [while in Congress]; many of them were not there," Taft said.

He said a typical legislative activity for him was the passage of an amendment in 1977 that protected amusement and theme parks -- his clients -- from minimum wage and hour laws. Taft mapped out the strategy and prepared material for executives from theme parks around the country, who came to Washington and fought their own fight. Taft himself contacted no members, he said, knowing from experience that constituents make a stronger impression than ex-senators.

Even if connections are no substitute for ability, they are not without value. Ex-members generally agree that, as a matter of courtesy, they get quicker access to sitting senators and representatives, a higher place on hearing agendas if they wish to testify, and more ready answers to questions about vote counts, proxies or likely amendments.

Former House Ways and Means chairman Wilbur Mills (D-Ark.), for instance, capitalized on congressional courtesy when he represented Encyclopaedia Britannica Co. in its efforts to ease a Federal Trade Commission rule governing the behavior of its door-to-door salesmen.

Mills would set up appointments with his former colleagues, make a brief speech, then introduce Britannica lawyers to make the case in detail. Mills seemed only "roughly familiar" with the specifics of the problem, said a House aide who sat through one such briefing. "My assumption is his name was being used to gain the appointments."

When the issue came before the Senate Commerce Committee, Chairman Howard W. Cannon (D-Nev.) let Mills sit on the dais with committee staff and contribute informally to the proceedings. Mills did not get the law changed as he wanted, but congressional interest helped win his client a new hearing at the FTC, according to commission sources.

Former members also have the privilege of access to the floor, the members' gymnasium and dining room and other sanctuaries closed to civilian lobbyists. House rules forbid lobbying on the floor, but Senate rules do not and staffers said they have seen ex-senators circulating while the Senate considered legislation of interest to their clients. Exploiting this privilege to lobby is rare and risky, because many members consider it improper.

Special access, however, helps ex-members maintain their status in the fraternity. Quasi-official events, social gatherings and fund raising also keep alive a degree of camaraderie some ex-members feel gives them a short leg up on other lobbyists.

Mike McKevitt, a one-term GOP congressman from Colorado who now lobbies for the National Federation of Independent Business, goes sailing with members on the Chesapeake Bay, has attended Super Bowl games with Rep. Jack Kemp (R-N.Y.) and dines in the homes of former colleagues.

Roger H. Zion, a former Indiana Republican congressman who lobbies for a variety of clients, still attends a weekly House prayer breakfast.

"When you're talking to somebody you've played paddleball with or played in the Republican-Democratic golf tournament with, or seen regularly in the Capitol Hill Club, there's no question that helps," Zion said.

Some former members remain politically involved, too, which keeps them on familiar terms with congressional incumbents.

O'Hara, for example, was a vice chairman of the Kennedy for President campaign and a prominent participant in the effort to force open the Democratic convention.

On the Republican side, the Reagan campaign enlisted several ex-member lobbyists in campaign and transition roles. One of them, Kuykendall, was a campaign liaison with Congress and has helped plan inaugural festivities. Asked if his participation would be good for his lobbying business, Kuykendall exclaimed, "Hell, yes. People will hire you just because of who you know. This is the first time since I left Congress it was a good time to be a Republican."

If a member has built up reservoirs of trust and credibility during his public career, he may be able to tap them as a lobbyist.

O'Hara, for instance, established himself in Congress as a leading advocate of organized labor. When the Business Roundtable hired him to argue the corporate viewpoint on a regulatory reform bill, O'Hara was able to approach the AFL-CIO and conduct one-on-one negotiations.

The AFL-CIO was allied with consumer advocates in support of regulations the business community wanted relaxed. O'Hara attempted to win labor away from that alliance with a compromise, and consumer advocates say he nearly succeeded.

Most former members who lobby specialize in areas they handled while in public service. Frequently they end up selling their skills to the people they used to oversee and regulate. A few prominent examples:

Eight-term Rep. Fred B. Rooney (D-Pa.) made his name in Congress as an advocate of the railroads. When the voters retired him, his first client as a consultant was the Association of American Railroads.

Rep. Philip E. Ruppe (R-Mich.) went from the ranking minority position on Interior's mining subcommittee to Amax Inc., a metal company.

Another Interior member, Lloyd Meeds (D-Wash.), who was the author of much public lands legislation, has subsequently lobbied for the state of Alaska and timber interests on public land issues.

Rep. Brock Adams (D.-Wash.) was specially suited to represent truck and railroad users interested in legislation to deregulate those two modes of transportation. Besides handling transportation issues on the Commerce Committee, Adams served as President Carter's first secretary of transportation.

A Transportation Department official said Adams, as a lobbyist for commercial rail users, played a major role in selling the House on a rail deregulation bill he helped devise as a Cabinet member. He opposed his former Transportation Department colleagues on the trucking bill; representing grocery manufacturers, he tried, without success, to keep price controls for grocery stores that transported their own goods.

There are a few restrictions on former members of Congress returning to reshape legislation they handled while on the public payroll.

The 1978 Ethics in Government Act requires a one-year cooling-off period before certain ex-government officials can lobby their former agencies on matters they handled, but the law does not apply to members and Capitol Hill aides.

The Senate has incorporated a similar one-year hands-off period into its rules, but the effect is largely psychological: Senate rules are only binding on current members and staff.

While some outgoing members of Congress said they find the revolving door distasteful, Congress has been leery of tightening restrictions on the flow between government and the lobbying trade, fearing barriers that would discourage qualified people from entering government. In 1979, the ethics law was loosened because of that fear.

"I've always looked at the revolving door argument with great skepticism," said Eckhardt, who is well regarded by reform groups. "It's one of those apparent reforms that is not a reform at all."

"Look, everybody in this life essentially sells their knowledge and experience," said Rep. Bob Carr (D-Mich.) "I don't see why members of Congress ought to be excluded from that club." Carr lost his reelection bid in November, but said he did not have any firm job offers.

Most former members seem to pick work compatible with the views they held in Congress. But sometimes the marriage of ex-members and clients seems a bit unusual. Liberals seem especially likely to hear charges that they have "sold out."

Brock Adams, for example, has been criticized by save-the-whales activists because his law firm represents fishing interests of Japan, a major violator of international whaling rules.

Adams said in an interview that he does no "substantive" work on the Japanese account, though he has briefed members of the firm who were presenting congressional testimony for the Japanese. He said his firm was hired to deal with the purchase of fish caught within America's 200-mile fishing zone. "We don't have anything to do with whales at all," he said.

To a man, former members who lobby say they would not represent an interest that clashes with their conscientious beliefs. But as O'Hara points out, only a small portion of a member's votes grow out of deep personal conviction.

"God knows, I didn't feel strongly about 90 percent of the stuff I voted on [in Congress]," he explained. "It was just a matter of going along with what the district wanted or what the party wanted."

O'Hara said his clientele sometimes has led him into positions he might not have taken as a liberal Democrat in Congress. For example, he worked for timber interests trying to maintain logging rights in the landmark Alaska lands bill. On the other hand, he said, "If somebody asked me to repeal OSHA [the Occupational Safety and Health Act], I'd say, 'I think you need some other firm.'"

Being a former member doesn't automatically make a person a saleable lobbyist, and there are some who find it a disadvantage.

"I tend to find a former member doesn't make all that good a lobbyist," said Kenneth E. Davis, a former Senate aide who represents Rohm and Haas Co. "A lobbyist has to do the grunt work. Members of Congress have staff to do the grunt work."

Attorneys in three Washington law firms -- all former congressional staffers -- said they looked over the 1980 crop of outgoing members and decided they were not interested. The lawyers asked not to be quoted by name.

"A lot of former members of Congress don't understand the mechanics of the procedure well enough to get very far," said one. "A lot of them just like to float around seeing their old buddies, hanging out in the speaker's lobby."

Former members who make the transition to lobbying, it can be a comfortable life. The money is better (roughly, from $75,000 a year for a trade association job to $200,000 or more at a high-powered law firm). The pressure is reduced.

"It's a much saner life," said former Rep. McKevitt. "You're not barreling to National Airport every Friday night to catch the last flight to Denver. Your weekends are your own. You can spend time with your family. You don't have to keep saying goodbye to your friends."

Some ex-members, like former Sen. Frank Moss (D-Utah), admit they miss Congress deeply. The majority left Congress against their will and some admit to feeling, as one put it, "like a firehouse Dalmatian when the alarm bell goes off" each time an election approaches.

But many, after the initial separation pangs, say they are relieved to be out of an institution they see as declining in prestige, hamstrung by special interests and simply not much fun anymore.

Fred Rooney, for one, recalls a carping press, demands to explain every vote to one special interest or another and pressure on his time and attention.

"I wouldn't take that job if I were appointed and the salary was doubled," he said.