Rep. John Brademas (D-Ind.), the majority whip, is probably one of the few congressmen to have a major American artist like Robert Rauschenberg design a campaign poster for him.

He is also one of few congressmen who regularly goes to see the performing arts. It's commonplace to see Brademas at the theater, ballet or symphony.

He's on friendly terms with composer Gunther Schuller, singer Beverly Sills and painters Robert Motherwell and Rauschenberg. Some of them have come here to testify on legislation the congressman has proposed.

Brademas says he doesn't think of himself as the congressman for writers and artists because he's involved with a brad range of social problems.

Poet Kenneth Rexroth, who describes himself as an anarchist, calls Brademas the "most likeable congressman I know."

The congressman calls himself an electric hin his artistic tastes, "I like rock and I like Bach," he says. He listens to Elton John and John Coltrane, Herbie Mann and B.B.King.

Brademas, 50, was chief sponsor of the 1975 Arts, Humanities and Cultural Affairs Act, which extended the life of the National Arts and Humanities Endowments for four years.

He was principal sponsor of the 1976 Museum Services Act, which provides grants to museums for exhibits, educational programs, curatorial training and general operating expenses.

Such legislation marks him as a true friend of the arts. Does this legislation come out of a particular vision Brademas has of where the arts should be in this country?

"Some of this may sound like cliches," he replies, "but I think it's important that in wanting to support the performing arts that we don't lose sight of individual artists in our desire to keep theater companies and symphonues alive.

"That's always a preoccupation of mine: that we'er not doing enough to help the individual creative artist, whether painter, writer, dancer or poet.

"Second, I think this is true of both endowments: that it's important to encourage quality while at the same time trying to insure as much accessibility as possible. You always have these twin objectives when you get into areas like the arts and humanities and education."

Says the Indian Democrat: While I think that we as legislators have got to be at some accountability from expenditure of Public dollars, at the same time we ought to be self-denying to a considerable extent so that we don't have our hand trying in some unwarranted way to guide the arts.

"The danger in the present structure as I see it is that those of us in Congress that are active in these matters will be so sensitive to keeping our hands off that we will allow appointed bureaucrats to come in and fill the power vacuum. That can lead to trouble. I think the arts are flourishing. Our problem is to pay for them."

Brademas, who has paintings by Rauschenberg and Motherwell and Yugoslavian peasant artist hanging in his Georgetown home became interested in art while growing up in Mishawaka, Ind. His mother, at teacher who today at age 80 still reads seven newspapers every day, encouraged his interest in a variety of subjects.

His father, a Greek immigrant who came to this country about 1914, and his maternal grandfather talked to him about politics.

Although of Greek ancestry, Brademas became a Methodist by going to church with the family's housekeeper. He credits the Methodist church for giving him a strong sense of social concern and responsibility.

While at Harvard between 1946 and 1949, after service in the Navy, Brademas considered going into the Methodist ministry. Theologian Rheinhold Niebuhr's Christian interpretation of human nature and politics in a democratic society made a strong impression on him.

But while taking a doctorate in social studies as a Rhodes Scholar at Oxford, he became interested in the political life. His dissertion, "The Anarcho-Syndicalists in Pre-Revolutionary Spain," examined the role of the anarchists in bringing on the Spanish Civil War.

Once back in the States, he taught political science fora year at St. Mary's College, a small women's school near Notre Dame University.

The dissertion was published in book form in Spain in 1974. The congressman says he's constantly looking for time to edit the English manuscript. He had planned to use the Easter recess for editing purposes, but he went to China with a congressional group.

He worked for Adlain Stevenson in the 1956 presidential campaign and also ran a losing campaign for congress in that year. Two years later he was elected to the House and has been there since.

One of Brademas' constituencies is the education community. As chairman of the House Select Committee on Education, he has helped draw up or sponsor several major education acts.

Brademas was appointed majority whip at the beginning of the current congressional session. His job is that of chief vote counter in the House for the Democratic party. He watches how members vote and feeds them information that would attract them to the side of the leadership.

He is known as a man who mixes with people well. He represents the Third District of Indiana, which is largely blue collar. Brademas is at home with the Rotarians in South Bend as well as the intellectuals at Notre Dame.

As a bachelor, Brademas has the reputation of being a swinger. He is fequently seen in the company of attrative women.

Does he dislike the reputation?

"The thing is in this city if you are a member of Congress and you're not married and you go to a dinner of some embassy, and you go to two or three dinners a week, well, you're going to have people say that," he explains.

"I work hard and I like to work hard. I think that's a central fact. That particular characterization is something I guess I've let roll off my back."