On Capitol Hill, in the federal bureaucracy, among civil rights activists and real estate developers, the name Cushing Niles Dolbeare is synonymous with housing assistance for low-income people. Dolbeare, 55, is founder, president and half the permanent staff of the National Low-Income Housing Coalition.

"Cushing is one of the most effective lobbyists I've ever met in Washington," said Peter Harkins, staff director of the Senate Banking, Housing and Urban Affairs subcommittee.

Dolbeare and her coalition are credited with pushing through Congress many of the low-income housing improvements passed since 1974 when the major housing assistance program, called Section 8, was adopted. In fact, it was an attempt to make sure that legislation paid attention to the needs of the poor, that Dolbeare, in 1974, got representatives of housing, labor, civil rights and charitable organizations to form a loose "no-name coalition" on low-income housing.

"In 1974, it seemed nothing could be worse than the situation then," recalled Dolbeare. "Of course, we had no idea then how bad things would get under Ronald Reagan."

Back then, President Nixon merely called a halt to all new low-income housing activity by placing a moratorium on all federal housing aid programs in 1973. Now, Dolbeare and colleagues contend, Reagan wants to dismantle the existing programs by ending Section 8, withdrawing commitments for 300,000 of 700,000 housing units approved for subsidy but not yet built or rehabilitated, selling off property owned by the Housing and Urban Development department and raising the rent for low-income participants in the program. She figures housing would bear 37 percent of the cuts in the fiscal 1983 federal budget.

"Low income housing is under siege," said Dolbeare. "Most people totally underestimate the extent of the danger. The Reagan proposals are so far reaching, even if he gets half of what he wants in Congress, it would represent a tremendous loss."

What Reagan and like-minded members of Congress say they want is to switch the focus of housing aid from the apartment unit to the family. In the past, most federal aid for housing built or rehabilitated housing units. Reagan believes this construction is too expensive so he wants a voucher system that would subsidize the family to go out into the private market and obtain an apartment or a house like any other household.

Dolbeare and members of her coalition support a voucher system. In fact, Dolbeare called for one as an entitlement for the poor long before the current administration was in office. But she and others say the subsidy levels proposed are far too low. Also, they don't believe the federal government can get out of the housing production business because private developers just aren't building rental apartments on their own.

Dolbeare began the coalition's campaign against the Reagan plans last December after news of dramatic budget cuts leaked out. Using the "sign-on letter," a tactic she believes the coalition pioneered, she sent a letter to the president asking him to reconsider the cuts, signed by 111 national organizations and 1,500 state and local groups.

"We had hoped to get 500 signatures if we beat the bushes for them," she said. "But we were swamped with calls from organizations wanting to sign on." She sees that grassroots interest as a very good sign because she believes that only the low-income housing constituencies can really influence Congress.

That won't stop her from using all the lobby techniques at her disposal, of course. Once the budget committees and the housing subcommittees call hearings, Dolbeare will troop before them, armed with facts, figures and analyses of alternatives. She'll start off asking Congress to expand the current programs, although she knows that has no chance at all. "I think it's a mistake to tailor what you try to achieve by what you can achieve," she said. "So we'll say what we think needs to be done." Once the committees begin to write their own bills, however, "we'll work within the realm of the achievable." But she's not particularly optimistic about what is achievable for low-income housing this year.

Some of her colleagues disagree. "Last year it was just about impossible to get anywhere," said Henry B. Schechter, director of housing and monetary policy of the AFL-CIO. "But this year, I'm hopeful Cushing and others can make some headway because housing is down a great deal."

Florence W. Roisman, a Washington housing lawyer for the poor and long-time friend of Dolbeare's, is even more optimistic. "Because of the severity of the attack, the administration is building a consensus that hasn't existed for 40 years," she said. "It's bringing everybody together."

The ability to bring people together is one of Dolbeare's exceptional talents, say those who know her best. "Cushing is always looking for a basis for agreement among people," said Roisman. "She gets people to focus on what they can agree on and respects the issues they can't agree on."

Charles Edson, a housing attorney who represents builders and developers, agrees. "She's able to bring in people with widely differing views. We have extended ourselves to work with Cushing," he said. Both Rosiman and Adson sit on the coalition board of directors.

Dolbeare's attempt at consensus building extends beyond the coalition to Congress where she assiduously works both sides of the aisle. Because most of the coalition's proposals would expand federal housing programs, the most receptive members of Congress generally have been Democrats. But in 1979, when it became obvious to Dolbeare that federal aide was being cut back, she supported a measure sponsored by Sen. William L. Armstrong (R-Colo.) to limit eligibility for assisted housing to households whose income was half of the local average. Again, in 1980, the coalition worked with Sen. Jake Garn (R-Utah) to kill a proposal for middle-income housing assistance because it would have cut into the aid for the very poor.

Perhaps Dolbeare's most obvious bit of bipartisanship was to obtain the services of former Republican Massachusetts senator Edward Brooke, as chairman of the coalition from its incorporation in 1978 until this year.

Dolbeare points proudly to the fact that in the last two years, members of Congress of both parties have quoted coalition documents during debates on the floor more often than information from any other lobby group. Others say that has less to do with bipartisanship than having the sharpest analyses around.

"If I want to know what's going on in housing, what people think, what the numbers are, she's the one I call as a resource person," said Albert Eisenberg, the minority staff director of the Senate Housing subcommittee.

Dolbeare says she knows so much because even though she's been a lobbyist for only eight years she's been in the housing game for 30 years. "I'm probably one of the oldest people still around in housing," she said. She started out as assistant director of the Baltimore City Planning and Housing Association in September 1952, "but I never made a real commitment to housing until two or three years ago," she said. "I cared more about social justice and providing people the opportunity to fulfill themselves than I ever did about bricks and mortar."

In 1956, she went to work for the Philadelphia Housing Association where she stayed until 1967 when she became a housing consultant, "which is another way of saying I became unemployed," she said.

Working 60 hours a week for the coalition, Dolbeare considers herself barely employed. "How she is able to operate on such a shoestring constantly amazes me," says Andrew H. Mott, vice president of the Center for Community Change, and the coalition's new chairman.

The coalition's 1982 budget is $142,000, but Dolbeare is skeptical that the organization will be able to raise that amount. Coalition headquarters are in the converted garage behind Dolbeare's Capitol Hill townhouse. The staff consists of Dolbeare, Kate Crawford, her assistant and a computer-word processer that maintains the mailing lists and does the bookkeeping.

Despite her limited resources, Dolbeare would be the one to turn things around, if anyone can, her admirers believe. "She is so patient and so persuasive," said Sandra B. Solomon, executive director of the Neighborhood Coalition.

Dolbeare's major concern in the coming months is a presidential veto if Congress comes up with a more generous program than Reagan wants.

"It may be possible to persuade the administration to change," said Dolbeare. "They are realists. They're wrong, and they're going to have to recognize that their position is wrong and at some point, change."