ROLLA, Mo. -- The widow of Democratic Missouri Gov. Mel Carnahan said Monday she will accept appointment to the U.S. Senate if voters choose her late husband over Republican incumbent Sen. John Ashcroft in next week's election.

"I decided to do what I think Mel would want all of us to do, to keep the cause alive," Jean Carnahan, 66, told a news conference at her family's farm.

The Missouri seat is one a half-dozen across the country the Democrats consider key in their attempt to regain control of the Senate. The race was tossed into turmoil Oct. 16 when Carnahan was killed in a plane crash near St. Louis while campaigning.

The race had been a tight one but some published reports have indicated Ashcroft could be outpolled by his late competitor on Nov. 7. The latest Reuters/MSNBC poll concluded Carnahan was ahead of Ashcroft 50-43 percent.

Carnahan's widow had been lobbied heavily by party officials to agree to the move, one which they said would give voters a clearer picture of who they were really voting for if they chose to support the late governor next week.

Carnahan's name remained on the ballot as the Democratic candidate, and party faithful were being urged to vote for him despite his death, to keep his campaign alive.

Under the plan hatched by party leaders, Jean Carnahan would serve for two years, after which the seat would be filled by a regular election.

The crash in which Carnahan died also killed his son, Roger, who was piloting the plane, and long-time aide Chris Sifford.

Republicans in the state have raised questions about whether Carnahan's election, should he outpoll the freshman Republican Ashcroft, would be legal.

There is a long history of widows succeeding their husbands in U.S. politics. Maine Republican Margaret Chase Smith, the first woman elected to both houses of Congress, succeeded her husband in the House after he died in 1940.

Muriel Humphrey was appointed in 1978 to serve the remaining term of her husband, the late Minnesota Democratic Sen. Hubert Humphrey.

And there are three current members of the House of Representatives who succeeded their late husbands -- Mary Bono, a California Republican; Lois Capps, a California Democrat; and Jo Ann Emerson, a Missouri Republican.