BARBARA JORDAN. The first black woman everything. The symbolic orator from the South with the stained-glass voice who in 1976 electrified TV viewers and milling delegates alike as the Democratic National Convention keynoter.

The freshman representative who achieved national fame during the impeachment proceedings with her "we the people" anti-Nixon speech. The black woman who wouldn't take anything less than attorney general in President Carter's cabinet.

The beneficiary of adulatory media coverage which overstated her power at the time, Jordan now is in an anticlimactic lull, becoming a victim of that past instant stardom. People are beginning to ask the one question politicans loathe above all: "Whatever happened to . . . ?"

Trying to find the answer to what has happened to 41-year-old Texas Rep. Barbara Jordan is not so simple as it might seem. Some on Capitol Hill say contemptuously that she is doing nothing substantive; others say she is an impressive behind-the-scenes hard worker.

Many liberals, blacks and women on the Hill have been angered, not so much with what Jordan is, but because she does not fit their vision of what she should be. To them, she is a paradox who votes liberal most of the time but pals with the conservatives. They see her ambition leading to cautious politics at the expenses of issues.

In lofty oratory, she capitalizes on being black and female, the symbolic importance of her presence. The "something special" about the Democratic convention was that "I, Barbara Jordan, am a keynote speaker." And yet she remains independent of the black and women's caucuses and rarely pushes civil rights and women's legislation on the House floor. In fact, the day when Jordan speaks out on anything on the floor is rare. If anything, the criticism of her moderate approach has grown this year.

"Maybe I'm not loud enough for them," she mused in an interview. "To be effective to some people - whether you know what you're talking about or not - you have got to talk. I just don't see it that way."

Her detractors, however, continue to criticize her performance in committees - always with a not-for-attribution caveat.

"On Government Operations, it's as if she's not there. She did zero work on the consumer protection bill, for example. She may vote right, but she doesn't work for things," said one member.

Another colleague on the Steering and Policy Committee said, "I didn't see her active on any of the House reform pieces or much of anything else."

A leading Democrat on the Judiciary Committee said, "She's just not around much and therefore you get little continuity. I'd give her a C in effectiveness." Common Cause lobbyists say it would not occur to her to push issues - "She displayed no leadership, for example, on financial disclosure or lobby disclosure bills." A White House aide said, "She seems to have withdrawn. It hasn't occurred to us to go to her on anything. I certainly didn't see her active in the creation of the Energy Commission, for example."

And Black Caucus member John Conyers Jr. (D-Mich.) sputters his discontent by innuendo: "Look, I can't talk about this. If I was going to retire, I'd tell you what I think." "A Ceremonial Leader"

JORDAN GETS high points from others for precisely the same reasons some knock her. Several members agreed with the assessment of one Government Operations colleague: "She is preserving her credibility by not pushing herself into the limelight on national issues. She's highly respected because she is authoritative, intelligent, does her work and doesn't ride the crest of her publicity. She was a real leader in getting civil rights into revenue sharing."

A Judiciary Committee staff aide disagrees strongly with those who say she is not effective. "Most of those who come here with their eyes on the stars are usually inept when it comes to the nitty gritty of getting things done. But when Jordan comes up with an idea, you pay attention. Jordan may not be an 'architect' but she sure as hell is a 'mechanic' who can put things together."

Yvonne Burke, the black California congresswoman, said, "Not everybody is a fighter. Some of us run around in circles taking on a number of things. She's a very ceremonial leader."

Jordan is the first to agree that she picks her shots carefully and tackles but a few measures at a time. She points to only two measures - the same ones others always mention - as her major accomplishments in five years in the House. Both were two years ago, and involved civil rights legislation. One extends the Voting Rights Act of 1965 to cover Mexican-Americans in Texas. "That was unpopular back home but it made eminent good sense," she says. The second was adding anti-discrimination clauses to revenue-sharing legislation and the Law Enforcement Assistance Act. Her job of "major importance" now is "trying to graft anti-discrimination legislation onto all Title 6 programs."

Jordan says she operates best "one-on-one," using the sledgehammer of reason. When colleagues argued that there already was a Civil Rights Act and her anti-discrimination amendments were unnecessary, Jordan would say, "What if the blacks, women, Mexicans . . . what if they say, 'You're putting me on with all your pretty words?' Even though there is a backlash shift to the right, it is still not popular to deprive one of basic civil rights. So you deal with that. No one wants to be branded."

But when the probability of losing a greater than winning, Jordan is not necessarily a front-runner. Interviewed before she came to the Hill in 1973, she said, "I hope to be able to push for national health legislation." Asked what Jordan has done toward that goal, an aide paused, then said, "Well, we haven't worked on that bill. Reality is that it's just not feasible. You can't get it enacted without the support of the administration and doctors." Others, not so pragmatic, have pushed health insurance bills if for no other reason than to engender debate. In Demand as Speaker

THE SUBJECTIVE and diverse comments regarding Jordan's effectiveness point up the folly of trying to define "leadership" and "power," amorphous qualities on the Hill unless one has a key chairmanship or leadership post.

The one who makes headlines often possesses neither. The classic example was Belia Abzug, the New York congresswoman who could get off an airplane in Guam and be instantly recognized. Despite her international reputation, she had trouble getting things done on the Hill.

Some vital ingredients for clout are having something other colleagues need and want, the ability to put together a coalition on a vote, a taste and feel for compromise and what the consensus will be. Something Jordan has that puts people in her debt is her national adulation.

"There isn't a colleague who doesn't want her to speak for them at a fund raiser," says her good friend, Rep. Charles Wilson (D-Tex.). Yvonne Burke, who has all but announced plans to run for attorney general of California, said she was going to ask Jordan to speak for her.

Jordan says, "If you are respected by your colleagues, if you are consulted, if your advice is sought, that to me is power." She clearly feels she possesses that kind of power, through her one-on-one persuasion and "knowing the subject matter hopefully more thoroughly than anybody else. That's a real lever."

The most radical brick thrower of the 1960s has learned the value of compromise, but Jordan's style is not often, and, probably never will be, understood by non-Southerners or, for that matter, Southern liberals.

She is not just compromising when she laughs and jokes with and seeks out Southern conservatives. She likes them. And they are comfortable with her. Jordan is "safe." It's just a natural affinity," she says.

Rep. Joe Waggonner (D-La.), who has an Americans for Democratic Action rating of 0 - Jordan has 75 - counts her a close friend. "She is not a ranter, a raver, a radical," he explains. "None in our crowd would ever say a thing bad about her - and the chairmen all just love her. Probably her best friends are white Southerners. Now Andy Young did not enjoy that as much. It seeped through that he was more a champion of blacks per se than he was [of] Americans as such. Deep down there is probably not a proud feeling between Barbara and Andy."

While Jordan says she "hasn't ruled out" running for Republican John G. Tower's Senate seat next year, Wilson thinks that Jordan feels "deep down a black could not win statewide in Texas. But I feel she'd get every black and Chicano vote plus a lot generally regarded as against civil rights. A lot of people are looking for a chance to prove just to themselves they're not racist - and Barbara does not inflame them like some." Role of Black Caucus

JORDAN ALWAYS has been a good Texas Democrat who knew that the only way to get anywhere in Texas Senate since Reconstruction, she says, "I singled out the most influential and powerful members and determined to gain their respect."

Jordan has been walking a chalk line ever since. She is enormously popular in her heavily poor, black and Mexican-American district, yet by not taking shouting stands she keeps her ties with the conservative whites who run Texas politics.

Along with other liberals and women, she voted against cutting Medicaid funds for abortion and even influences some of her good-ole-boy colleagues.

Wilson says, "I'd be afraid to vote wrong on abortion. Barbara's wrath is more than I can bear." Yet her eloquent words are seldom raised on the issue. A friend said, "She could never speak out on abortion and run statewide in Texas."

While Jordan, with her intelligence and sometimes formidable manner, was winning through intimidation long before any book on the subject was written, her friends say there is counter-intimidation from the Black Caucus. "That's her pressure cooker," says Waggonner. "She can only go far without destroying communications with the Black Caucus."

And Wilson says, "She doesn't like to be the only black to vote a certain way. She felt she was letting down the unemployed teenagers in her district when she voted against the teenage differential in minimum wage, but she didn't want to be the only black not to." Jordan says Secretary of Labor Ray Marshall convinced her that teenagers paid less than minimum wages would displace adults seeking jobs.

Counter-intimidation or no, some of the young turks in the House feel she has sold out. "She's worked damn hard to be liked by Texans and Southerners and that, as far as the progressives are concerned, renders her useless," said one.

Her friends counter that Jordan's contacts are the "right" ones. House chairman who can help her in the future do not overlook the fact that, Wilson says, "she is very strong in one of the biggest Democratic delegations. With anybody who makes any difference, she is a friend."

One of the closest of these was her mentor, Lyndon Baines Johnson, and she repaid him with loyalty, supporting the 1968 Democratic platform plank praising President Johnson's Vietnam policy. She told the Wall Street Journal later, "That plank probably resulted in further killing and dying, but I felt it was important for Texans to be supportive of their man."

Such a harsh example of practical politics leads people to call Jordan a female LBJ. But Rep. Bob Eckhardt (D-Tex.) brings a telling dimension to the picture. Her moves come not just from calculation, but from years of Texas acculturation.

"To begin with, Barbara's voting record is so much better than the rest of the Texas delegation it's hard for me to criticize her," says Eckhardt, the only Texan consistently against the big oil interests.

"In Texas, being black and female and in modest circumstances, I think you've got to forgive a considerable procedural cautiousness that may be called conservative. And maybe she just isn't all that liberal. She is a product of her background." Keeping the Lid On

JORDAN'S LIFE began in Houston's 5th Ward, the home of lower-and middle-class blacks, where she lives with her mother when she returns to Texas. From her Baptist minister father, the late B.M. Jordan, she learned control. "My father was a strict disciplinarian and I always had to keep the lid on no matter how angry I got," she once said. Keeping the lid on is still a Jordan trait.

Jordan also learned that the whites lived somewhere else. In her totally segregated world, she saw the evidence of limits to one's life at every turn - but she somehow escaped the embittering disillusionment some blacks feel.

"I can still get goosebumps when I hear 'The Star-Spang-led Banner,'" she once said.

She did not rebel - joining the staid National Association for the Advancement of Colored People rather than Selma marches or Houston sit-ins.

Her father insisted on As, not Bs, and wanted his three daughters to become respected music teachers. Two of them did, but Jordan wanted more. She once thought of being a pharmacist but, as she has remarked, "Who ever heard of an oustanding pharmacist?"

As a high school sophomore, she heard a black woman lawyer speak and made up her mind to become lawyer. At the all-black Texas Southern University she excelled at debate on a team that beat the best white teams in the country, including Harvard's. Jordan went to Boston University Law School - the only woman in her class.

Politics got to her early. "I never have given the practice of law a real good chance," she says today. "I was always running."

She failed in two attempts for the Texas House and considered leaving Texas for a state where black women candidates would have a better chance. But after the Supreme Court's one-man, one-vote ruling, the state legislature divided Houston into electoral districts and, in 1966, Jordan won in a district that was 36 per cent black. Four years later, she was on a committee that redrew electoral districts and carved her present 48 per cent black congressional district.

Jordan's cozy relationships with LBJ and others in the Texas establishment led her opponent in the 1972 election, Curtis Graves, to call her an Uncle Tom, but Jordan swamped him.

In the Texas Senate, Jordan cosponsored the state's first minimum wage bill. Her votes today are pro-labor, but a leading labor lobbyist echoes the now familiar litany: "She's a very effective speaker for labor - but I can't remember a damn thing she's done or a bill she's introduced for labor up here."

When Jordan came to the Hill, the Judiciary Committee interested her. LBJ helped get her on the committee. No one could have foreseen it would become the pivotal springboard for Jordan's oratorical skills and subsequent national prominence. "Read My Record"

BARBARA JORDAN today is transformed from the woman who loomed before the cameras at the Democratic convention. She has lost an enormous amount of weight, some 100 pounds, which has prompted numerous questions about her health. It was done by design, she says, flashing a charismatic smile, "simply by not eating."

In addition to the intellectual assurance she always exuded, there seems now to be a confidence about her looks. Her formidable, aloof manner has eased. In private, her doomsday voice can turn folksy. On the floor, in her customary "throne" - the seat on the center aisle, three rows from the back - she laughs and offers dry quips to her buddies.

When a member made a reference on the floor to "I and my wife," she leaned over and said, "Well, it's easy to see who he puts first."

Jordan relaxes with friends by singing and playing the guitar, but has a minimal Washington social life. "I live in Texas. I'm into my work here."

"Those who know me know I am a good, kind, personable, loving human being," she says, with just a trace of a simle. Unperturbed by criticism, she says, "I just tell them to read my record."

One question about her "record" is why Jordan testified as a character witness for John Connally in the former Treasury Secretary's 1975 bribery trial. Wilson says, "Frankly, Barbara detests him."

Once again, she was obeying the code of Texas political loyalty. LBJ's widow testified for him. So did Jordan's friend, Robert S. Strauss, a longtime intimate of Connally's and then the Democratic national chairman who later would pick Jordan as the 1976 keynote speaker.

Jordan says today, "I just felt it was the right thing for me to do. I couldn't let my personal feelings for him prevail and prevent me from acting like a responsible citizen."

Nor does she view herself as selling out to the racists she's encountered in politics. Rather Jordan sees herself as a sort of emissary.

"If you can just focus on this person as a human burdened with all sort of junk - just as I am, as is everyone. Sometimes it's racism, hate, sarcasm. If you cut through and get to that person, he may toss off that excess baggage, I get through."

Jordan posesses a "subliminal power," stemming more from simply being Barbara Jordan than from anything she actually does in Congress. "It's just the whole notion of anticipated potential, an aura she commands," says a Republican colleague.

No one expects her to stay in the House, and Jordan herself says with crisp finality, "I don't think I came here to make it my life's work." Even her detractors do not reject the idea that her being moderate could lead someday to a vice presidential nomination as a safe black female. She does nothing to discourage the speculation.

Jordan today seems loose about her future. Hardly pleased at being used as a cosmetic token on Carter's vice presidential list, she shrugs, "It's part of the business."

She plays her cards so close that not even her friends know what she will do. She will make a decision about the Senate race "after I think things through at the end of this session." Some aides think that will be too late to rev up.

A judgeship might come, but later. "Once you put on one of those robes, your silence is enforced."

At one time she scoffed at the idea a black woman could become governor of Texas, and Wilson still rejects it: "They still like their governors in cowboy hats." But now, Jordan says quietly and positively, "That will occur." She gives no timetable.

For above all, Jordan has one quality to tide her over on her current plateau, a quality acquired growing up black and female in Texas: the patience to wait.She is going along, building up her influential friends and pile of chips, rocking no boats, waiting.

As her friend Waggonner says, "She sorta waits in the gap. She'll get her share of the pieces."