When Rep. George Collins (D-Ill) was killed in a plane crash almost seven years ago, his wife was offered the widow's mite -- the chance to run for his seat. It took the late mayor of Chicago, Richard Daley, to persuade Cardiss Collins this was her future. She won easily.

Yet for several years Collins was ill at ease with the jump from accountant to politician, frustrated at her own political naivete and feeling guilty because her son was growing up without her close attention. She kept a low profile.

No more.

Last month, a Navy admiral, facing a small contingent of congressmen on a junket through the Far East, was getting annoyed. Cardiss Collins, chairwoman of the Congressional Black Caucus and the only woman present, wouldn't let up in her criticism of the idea of registration for the draft. When the admiral refused to concede, Collins' strong voice began booming, her tone became strident. As the politicans began to squirm, the more senior Rep. Louis Stokes (D-Ohio) brought up a totally different subject. Collins glared briefly, then everyone sat back.

A year ago that wouldn't have happened. The near-showdown with the admiral was part of the new Cardiss Collins, a woman who has traded in her shyness for a more forceful voice and leadership role. In the eight months since she was elected to head the 17-member caucus, she's been expected to speak out in the tradition of that position. Reps. Parren Mitchell of Maryland, Stokes of Ohio, Charles Diggs of Michigan and Yvonne Burke, the former California congresswoman -- all aggressive politicians -- preceded her.

"In the last six years my biggest roadblock has been shyness. I was basically an introvert, but once people leaned I had something to say, I gained confidence. But it took a long time to come out of my shell and realize I was here, doing this alone," says Collins, 47. The first years after her husband's death were painful. Once she wept openly when she realized she was wearing the same dress she had worn to her husband's swearing in.

But so far this year, Collins has not appeared retiring -- confronting President Carter on the budget, speaking forcefully to House Speaker Tip O'Neill on the Mottl Amendment to ban school busing, then coordinating the defeat of the Mottl effort.

Her decision not to invite Jimmy Carter to address the annual Black Caucus fund-raising dinner tomorrow has raised questions about her political savvy. Instead of the invitation to speak, which the president has received for the past two years, Carter received a telegram -- as did all announced and anticipated presidential candidates -- to mingle tonight at the opening reception of the caucus weekend.

But Collins, her elbows on her desk, her annoyance obvious, replies, "He has nothing to say; that's my personal view. He has traded off black votes given to him in confidence. When he calls these summits, he ignores the Black Caucus. What about respect for our offices?"

She also noted at last night's Black Caucus party for Rep. Ronald Dellums (D-Calif.) that many blacks were watching with growing interest Sen. Edward Kennedy's possible candidacy, but that she herself was lukewarm on it.

Among her Capitol Hill colleagues, Cardiss Collins' sense of fairness and her poise are openly praised.

"During the Community Services Administration hearings, Collins said frankly that these were programs she cared about and that affected her constitents. But at the same time she looked very closely for areas where the government wasn't getting its money's worth," says Rep. Wayne Grisham (R-Calif.), a member of Collins' manpower subcommittee of the Government Operations Committee.

In the often-raucous meetings of the Black Caucus, Collins has taken a personable stance as moderator. Now, say the insiders, there are debates instead of arguments. "She is always properly assertive," says Charles Diggs, founder of the caucus. "She uses a general forcefulness but with a degree of sophistication that helps her recognize the personalities and views of the caucus. That's no easy feat."

This is especially true because her emergence is still a work-in-Progress, with more advances and setbacks ahead, until she can command attention given to other black leaders.

"She's quietly determined," observes Eddie Williams, president of a black think-tank, the Joint Center for Political Studies, who works closely with a country-wide netowrk of black officials. "Maybe she is too quiet, but that might only be a shortcoming in the role she plays right now."

Her lack of a strong public image until now resulted from her own background as one of the millions of blacks in the middle, not that over-examined underclass or the ballyhooed middle-class, a group that's traditionally moderate. An only child, raised by a domestic and a manual laborer in St. Louis and Detroit, Collins started as a stenographer, worked her way through college nights and rose through the ranks of Illinois civil service to become an accountant and a revenue auditor.

Her politics have been shaped by on-the-job training: As part of the Democratic machine in Chicago, as an integral worker in her husband's campaigns, as a representative to a tough district that once elected a dead man to Congress. Her district covers the Magnificent Mile of downtown Chicago as well as the scarred war zones of the black West Side.

She doesn't have the stirring speaking talent or moral tone that swept Jesse Jackson and Barbara Jordan into America's consciousness.

But what she does offer has a special place in American politics: A street-wise instinct that represents the pulse of the laundromat rather than primarily, the pluse of Morehouse or Howard. "The Black Caucus has 17 members and there's a place for all," says Collins. "I just don't think Cardiss Collins has to say everything for everyone."

When George Collins was killed in a crash at Chicago's Midway Airport on Dec. 8, 1972, his wife was trying to be both mother and father to their only child, Kevin, then 13. So when she received the now-traditional widow's condolence -- the party's offer to run her for his seat -- she balked.

"Kevin's security was foremost. Kevin knew the sacrifices; I knew the pitfalls. And Kevin didn't want to leave Chicago. So first I had to deal with his stability," says Collins.

Kevin, now almost 20, is a political science student at Howard University, a tall, husky man. He recalls, "When we discussed her coming to Washington, I told her, 'I want you to take his place, to keep the Collins name going."

So, in the midst of adjustment to being a widow, and a new career at age 41, Collins began the routine of the Chicago-to-Washington shuttle and suffered the guilt of being an absentee parent. Both Kevin and his mother talk openly about the disadvantages.

"I missed a lot of the guidance you need growing up," says Kevin, who lived with his grandmother. "The male guidance. When I started looking at girls, I didn't know who to turn to. But I don't think it was as much of a strain for me as it was for her."

Collins, a large woman who wears a flattering short Afro and wide eyeglasses, rests her elbows on her desk and plays with telephone messages and earrings as she talks. "The worst thing was suddenly looking around and discovering Kevin was a man. He had grown up without me," says Collins." When I returned to my district on weekends, I only saw him asleep. Then when he started dating I saw him at the doorway -- he was going out when I was coming in."

If she had to do it over, Collins says, she wouldn't have run for Congress. "I was lonely and alone. My son was alone. I regret that lost time." Now, she and Kevin and her mother share a townhouse in Cleveland Park. She spends her spare time reading (recently "shogun"), listening to jazz (Philly Joe Jones) and checking out live acts at the Pigfoot and Blues Alley. To work off tension, Collins does physical things -- she installed a new floor in her exercise room and put up wallpaper.

No Collins and her son have a relationship she describes as a friendship. The only sore point is the car. She has first call on the '78 Seville. "And sometimes our schedules get mixed. Trying to borrow the car is like borrowing the Rosetta Stone," says Kevin.

The Mottl Amendment fight and the Andrew Young resignation controversy illustrate the hit-and-miss nature of Cardiss Collins' political savvy.

On the Mottl matter, the caucus moved with lightning speed, touching all the bases in the House leadership and developing a strategy on the question of the amendment's constitutionality that attracted some conservatives.

But on the Young matter, the caucus bungled -- and hasn't lived it down yet.

When Andrew Young resigned his U.N. ambassador post, the House was in recess; four caucus members were in the Far East, the rest were scattered.Since many of the other black spokesmen, including D.C. Delegate Walter Fauntroy, were at a Southern Christian Leadership Conference meeting together, television cameras focused on them for reaction. They ran with the issues of the dismissal, the contact with the Palestinians and the state of black-Jewish relations. The caucus never caught up.

Collins, who was in Singapore at the time, regrets that a unified statement was never made. "By the time we all got back, the question was moot," says Collins. Even a news conference called within a week of the resignation was canceled at the last minute because the members weren't available.

"We decided to make a more subtle statement by having Andy Young address Saturday night's fund-raiser and tell his story," Collins says.

Collins also has caused herself some problems in standing by statements she made to the Zionist Organization of America on July 30, two weeks before Young's resignation. Her speech, circulated by the organization as a pro-Israel position, has infuriated several of Collins' colleagues.

Is contrasts sharply to the statements of others, such as Jesse Jackson and Gary, Ind., Mayor Richard Hatcher, who condemn Israel for its support of South Africa and criticize many American Jews for wavering on affirmative-action programs. In her speech Collins said the bond between the United States and Israel, "is cooperative and nonexploitive," and later said, "Israel's record in Africa reflects that non-exploitive nature I noted before." Collins describes the speech as "right down the middle."

Possibly the next stand by Collins that will cause some controversy is her frank desire to see Walter Mondale run for president. "Actually I have never been gung-ho Carter, and I was with Mondale the last time. But I think he's the middle of Carter and Kennedy," says Collins, warming up to her subject and resting her hands atop her head. "What I think should happen is that Carter should become a stateman and resign. And you would be surprised the number of people privately who are with me on this."