In 1970, when the National Endowment for the Arts (NEA) was five years old, its new chairman, Nancy Hanks, came up against one key member of Congress who was unconvinced about increasing funding for the agency.

That was Julia Butler Hansen, a Washington state Democrat, who was chairman of the House appropriations subcommittee that recommended budget levels for the NEA. It was important that she be convinced. "Mrs. Hansen said, 'I don't have any letters,' " Anne Murphy, then the NEA congressional liaison, recalled yesterday. "Nancy said, 'Letters? You want letters?' She had fliers put on every seat of every concert hall and theater in the country. Mrs. Hansen got stacks of letters, thousands, mailbags of them, in three weeks, maybe four."

Nancy Hanks died Friday night of cancer at New York's Columbia Presbyterian Hospital at the age of 55. In the eight years that she chaired the endowment, she elevated the agency and the cause of the arts to national prominence and established its constituency as a powerful and vocal political force. "She made the endowment into a national program," said Rep. Sidney Yates (D-Ill.), the current chairman of the House appropriations subcommittee on the Interior.

She was a sturdy woman with a knowing smile and a raspy, low voice that allowed a tinge of a Southern accent to come through. She was friendly and easily accessible to the endowment staff, which grew tremendously during her tenure. Although a staunch Republican, Hanks largely put aside personal politics and made the arts a bipartisan issue.

Hanks was a little-known figure--she had been working on study projects at the Rockefeller Brothers Fund--when Richard Nixon appointed her chairman of the National Endowment for the Arts in 1969. Her predecessor was Roger Stevens, the first chairman of the NEA and now chairman of the Kennedy Center. Nixon aide Leonard Garment asked Stevens if he had any suggestions. Stevens mentioned Hanks. "I said, 'I think she's a rather smart girl' . . . Nobody had even thought of her at that point in time. They were looking for some women for jobs."

Stevens' estimation of her turned out to be an understatement. With a formidable combination of political savvy and personal charm, she guided the NEA from a budget of $11 million in 1969 to $114 million in 1977, the year she left her post. "Never did I know Nancy to not be prepared," said Murphy, now the director of the American Arts Alliance. "She was obviously charming. She made being feminine an asset. She smiled and she batted her eyelashes. And she was tough as nails."

Along the way she won the admiration of artists and arts administrators all over the country.

But her most crucial win was the Congress.

"She handled the hearings before Congress in a brilliant manner," said Yates. "She not only was well-prepared with her budget . . . she was very conscious of recognizing the role of Congress in this matter. She made it a point to visit members of Congress and take care of their questions."

Hanks made sure she never was boring. She submitted written testimony to the committee and then, during her appearance at the hearing, talked about other things. "She was witty and thoroughly informed," said Yates, "the kind of administrator that members of Congress not only like to work with but one I was privileged to call a friend."

Once, at a reception at the Phillips Collection, Hanks displayed the endowment's logo, a stylized bird. "You may think it is a strange dove or a dead pigeon," she told the guests, who included National Council on the Arts members. "But it is, in fact, an eagle." And the crowd applauded.

"I remember several congressmen saying at parties that if only someone like her was running the State Department," said her friend, Charles Blitzer, who recently resigned from the post of assistant secretary for History and Art at the Smithsonian to become director of the National Humanities Center.

"She never took no for an answer," said Murphy. "She just pursued. She would invite members of Congress to a performance, go to their office, be sure to let them know when something was happening in their district. She'd read their daughter got married and she would call them. She courted them. In many ways, it was like a mating dance."

Frank Evans, a former Democratic congressman from Pueblo, Colo., and a member of the House Appropriations Subcommittee on the Interior, was someone Hanks cultivated:

"She'd never been able to convince him to support the arts," said Murphy. "She ran into him at a cocktail party once. He had on a silver and turquoise belt. She started talking to him about the belt and Indian art and preserving indigenous art. That was the beginning. She would find other things that he was interested in. She was nobody's dope. She wouldn't talk off the top of her head. She wouldn't meet with someone like Frank without having read about him and what he was concerned about."

She talked to Evans about water conservation in the West, one of his concerns. It might come up when Hanks encountered Evans at a reception or on the Hill. "She would make it come up," said Murphy. "She would just say, 'By the way, I read your speech at such and such a place and I thought it was good but it didn't address such and such . . .' "

She took Rep. John Murtha (D-Pa.), a subcommittee member and another who had to be convinced, to his first concert since his Navy days, according to Murphy. After Hurricane Agnes had devastated Murtha's home town of Johnstown, Pa., Hanks quickly awarded a chairman's grant of $10,000 to the orchestra there for a special day of music and festivities, Murphy recalled. Hanks also got private businesses to contribute. Impressed by the turnout in his town for the event, Murtha has been supportive of the NEA ever since, Murphy said. "Everyone knew she didn't do it for political reasons. She just saw a need and moved very quickly."

In the early '70s, when the NEA was in danger of a budget cut, Hanks and her deputy chairman, Michael Straight, mobilized all their forces. Straight gave a series of 10 or 12 parties, Murphy estimates, at his house and invited different members of Congress. Hanks called in some of the NEA's glittering reserves for active duty at these parties--National Council members Billy Taylor, Rosalind Russell and Beverly Sills were asked to come. Hanks found actor Eddie Albert, performing in a play at the National Theater, and asked him to come. And, of course, Hanks herself worked the crowd of congressional folk. "She talked to them and cajoled them and flirted with them and gave them sound information," said Murphy. "She would know any arts group and any grant of the district of any congressman."

In the end, "she must have turned around 100 or so people who would have voted for the cuts," said Murphy.

She was not a bureaucrat, not a sycophant. Neither did she go looking for a fight. She was shrewd. When being witty would do nicely, she was witty. Once, former Republican Congressman H.R. Gross from Iowa announced angrily on the House floor during a debate on the appropriations bill that the NEA was funding belly dancers. When Hanks was called for her reaction, she said she was sure it was a mistake and that he meant to say ballet dancers and that, yes, of course, the NEA funded ballet dancers . . .

Her 20-year battle with cancer (she had a mastectomy in 1962, according to a close friend and associate) also did not deter her. It was something that she rarely discussed with anyone. In India on a cultural mission a few years ago with Blitzer, "She ran me ragged," he said. "We went to Ahmadabad on a killingly hot day. I was sort of stumbling through it all, and Nancy was running ahead."

She was tireless during her endowment days, accessible to staffers, many of whose careers she nurtured and guided. Loaded down with briefing books--"she looked like a bag lady," said Murphy--she traveled around the country to see arts programs and arts administrators.

And when she resigned her post, though she stayed close to arts groups and was still a familiar face at opening nights, she enjoyed the freedom to walk out of a bad play at the intermission--which she and Blitzer did several years ago.

Her birthday was New Year's Eve, and she celebrated with a party each year at her Georgetown home. Wandering past the Richard Hunt sculpture in the living room, guests drank champagne and ate ham with mustard and marmalade sauce. Blitzer remembers meeting Rosemary Woods there one year and Sen. Charles Percy (R-Ill.) leading the group in a chorus of "Happy Birthday" another year.

Tomorrow there will be a memorial service for her at the Cathedral of St. John the Divine in Manhattan. It will be conducted by her cousin, the Rev. James Park Morton.

"She told me her father was so excited when she was born that he forgot to file for a last-minute tax deduction," said Murphy. "Nancy would have remembered."