Lynne Cheney, a senior editor at The Washingtonian magazine and wife of Rep. Richard Cheney (R-Wyo.), won unanimous confirmation from the Senate yesterday to be chairman of the National Endowment for the Humanities. Cheney was nominated by the White House after its first nominee, Peace Corps Deputy Director Edward A. Curran, was rejected by a Senate panel.

Cheney, 44, could not be reached for comment, but others greeted the news with enthusiasm.

"That's just great. She's first-rate," said O.B. Hardison, chairman of the National Humanities Alliance, an association for humanities groups. "I think perhaps she'll be one of the great leaders of the endowment."

Cheney will fill a post technically vacant since William J. Bennett left the agency early last year to become secretary of education.

The endowment is a federal agency with an impact and visibility far greater than its relatively small $132 million budget. The chairmanship has often served as a pulpit for an administration's views about the role of liberal arts in American life. The search for someone to do the job has often produced fireworks.

Cheney was nominated in March, shortly after the Senate Labor and Human Resources Committee rejected Curran. Curran made headlines in 1982 when as director of the National Institute of Education, he asked President Reagan to abolish his agency because of what he described as its liberal biases. He was later forced to resign. At his confirmation hearings, he was questioned about his credentials and political agenda.

Cheney has a PhD in British literature from the University of Wisconsin. She is the author of two novels, has worked as a college instructor and writes feature stories and a regular column for The Washingtonian. Colleagues describe her as intelligent, energetic and politically astute, qualities that some in the humanities community believe will help the endowment.

"She's got a humanities background, but she's also moved in a wider world," Hardison said. "Some people dedicated to the humanities tend to have a kind of tunnel vision. They don't stop to ask, 'How does this relate to the world?' "