Finally poised to give Federal Communications Commission Chairman Kevin Martin a Republican majority at the agency, President Bush was expected to nominate Richard Russell and Deborah Taylor Tate to be commissioners at the FCC, sources said late last week.

Senate confirmation of the candidates, which is expected after lawmakers return from their summer recess in September, will clear the way for Mr. Martin to begin pursuing a more aggressive agenda at the agency.

He has been politically handcuffed since President Bush named him chairman March 18 because the agency, which is authorized to have a total of five commissioners, has been deadlocked with two Republicans and two Democrats. The political party that controls the White House also controls three of the agency’s five seats.

Four seats are currently occupied, and one Republican seat is vacant. Another is occupied by Commissioner Kathleen Abernathy, whose official term has expired. She has made clear that she wants to move on.

The term of Democratic incumbent Commissioner Michael Copps expired at the end of June, but Mr. Copps is seeking a reappointment.

Mr. Russell, a biologist by training, is associate director of the White House’s Office of Science and Technology Policy. Ms. Tate, a lawyer, is a director of the Tennessee Regulatory Authority, which regulates telecommunications and utility firms in the state.

Despite his educational training in the life sciences, Mr. Russell has been working on technology issues for years, both at the White House and in previous posts with the House Committee on Science. Among his White House responsibilities is to serve as the liaison to the FCC.

Sources said Ms. Tate, who also has chaired the Washington action committee for the National Association of Regulatory Utility Commissioners, has the backing of Tennessee’s two influential Republican senators: Lamar Alexander and Senate Majority Leader Bill Frist.

Mr. Russell was confirmed by the Senate for his current White House job in 2002. Before being named to that post he served as the Office of Science and Technology Policy’s chief of staff and was with the House Science Committee from 1995 to 2001. He also served stints on the staffs of Rep. Curt Weldon, R-Pa., and Sen. John Seymour, R-Calif.

Before she was appointed to the Tennessee Regulatory Authority in 2002, Ms. Tate was director of the state and local policy center at Vanderbilt University. She was a senior staffer to then-Tennessee Gov. Don Sundquist, a Republican.

As recently as last Tuesday, another White House staffer-Mike Meece, special assistant to the president and deputy director of the office of public liaison-was poised to get the seat that now appears destined for Mr. Russell, sources said. But one industry source said Mr. Russell appeared to have a more relevant background for the FCC post because of his service as the White House’s FCC liaison.

The most important issue that is stalled until these seats are filled is the media ownership issue. The Supreme Court refused to review a decision by an appellate court that overturned most of the FCC rules on how many TV stations one company can own in the same market and regulations barring newspaper owners from also owning broadcasters in a single market. It is now up to the FCC to reconsider these questions.