When Barry and Roberta Levy bought the boarded up, shabby house at 909 M St. NW, two years ago, they could hardly believe that theirs was the same house that once was the fashionable and richly furnished address of one of the nation's earliest black U.S. senators.

The white couple could barely see the deteriorated interior of the distinguished 105-year-old home, where Blanche K. Bruce, a black Republican senator from Mississippi, lived during the 1880s and 90s, because tin plates covered all the windows in the four-story brick house.

Yesterday City Council member John A. Wilson (D-Ward 2) helped Levy, a young government official, place a small bronze plaque on his wrought-iron fence. The plaque says that the house is a national historic landmark, worthy of preservation.

"It's going to be a long and tedious process to see if we can make some of these neighborhoods livable again . . . It's good to have them moving in and trying to preserve the historical nature," said Wilson at the dedication service. The audience consisted mostly of other whites from the block who are renovating their own old but less prestigious homes.

The plaque reminds the neighbors and the neighborhood of the house's former elegance, an elegance that the whole block seeks to regain.

Rehabilitation in this block is already going on and is part of the general restoration and massive population shift now going on in Shaw, one of the city's worst slums. Young white couples are replacing poor black families in the area's large Victorian house.

"The house had been terribly abused, beaten and battered," Levy recalled yesterday. The roof leaked, the interior was chocked with trash, there were no bannisters, the furnace there were no banisters, the furnace was in disrepair and the walls were crumbling.

"We've tried to fix it up and fix it up right," Levy said. "It's an outstanding house, on an outstanding row, that was lived in by an outstanding man.

Levy, who paid $32,000 for the 10-room house, has spent an estimated $60,000 on renovations and will request $30,000 more from the National Capital Park and Planning Commission because, he said, "We're trying to do a sensitive restoration that preserves the historical and architectural character of the house."

The house is "part of an architecturally coordinated row of eight houses erected for speculation by William H. Browne in 1873 in the Second Empire style," according to the Joint Commission on Landmarks, which organized it in 1975.

The Second Empire style was imported from France after the Civil War and had as its most distinguishing characteristics; mansard roofs and bay windows.

Levy is not sure exactly when Sen. Bruce lived in the house. Bruce was elected to the U.S. Senate in 1874.

Bruce, born a slave in 1854, became the first black to serve a full six-year term in the Senate. When he was defeated for relection in 1880, he remained in Washington and served as the recorder of deeds (a post traditionally held by blacks in the city government), as a trustee of Howard University and as a member of the local school board. He died in 1898.

"Most of the house is still a mess," Levy said yesterday. But now it has a new kitchen, a new bath, new roof, a new furnace, new banisters (custom made to duplicate those of 100 years ago), new plaster moldings that are reproductions of those that were originally in the house, and new walls.

Tom Lodge, president of the Shaw Advisory Neighborhood Commission who lives in a restored house on Logan Circle, believes the decication of the Bruce house will help young blacks in the area.

"In a neighborhood where the role models are the pimps and the prostitutes on the corner, you need Blanche K. Bruce to show them the world is not as limited as it might seem," he said.

"The white middle class respects black history more I think than the poorer blacks . . . The more educated you are the more interest in history. If you are poor you are just trying to get by an interest in history is a luxury," he added.

Charles Richardson, who grew up around the corner from the Bruce house and is now president of the Shaw Planning Area Committee, does not oppose the white immigration. He hopes to help poorer blacks to stay by using city laws and city money to help black tenants buy the homes in which they live when a landlord decides to sell.