Mrs Carnahan says her husband's ideals are "part of her being"

Jean Carnahan's husband and son Roger died in a plane crash on 16 October, throwing the senate race into turmoil in a key state.

Mr Carnahan and his incumbent Republican rival John Ashcroft were running neck-and-neck in a hard-fought campaign at the time of his death.

Mrs Carnahan, 66, has never run for or held public office.

"With the support of my family and an abiding faith in a living God, I've decided to do what Mel would have wanted us to do ... to continue the fight for his ideals," said Mrs Carnahan.

In a statement released after her husband's death, Mrs Carnahan stressed that she shared his political vision.

"As I seek God's will for my life, I see each day more clearly," she wrote.

"I still believe deeply in the cause for which my husband lived and died. These shared values are a permanent part of my being."

Tough battle

Even though Mrs Carnahan has decided to enter the political arena, it will still be her late husband's name which appears on ballot papers on election day, 7 November.

How do you campaign against a ghost? - there's no precedent for this

Political scientist Richard Fulton

His death came after a deadline had passed for the replacing of candidates.

Republican volunteers have been distributing badges carrying the slogan: "I'm Still With Mel."

Analysts say the Republicans will face a tough battle to campaign against a newly-widowed woman and her popular late husband.

"How do you campaign against a ghost? There's no precedent for this," said political scientist Richard Fulton of Northwest Missouri State University.

The presidential candidates joined in tributes to Mr Carnahan

Some voters have welcomed Mrs Carnahan's move.

"Husbands and wives, they stand together, and she will keep going with what Mel Carnahan would have wanted to do," said Bobbi Slate, a 29-year-old a laundry clerk from Columbia.

But Tony Garcia, 62, a retired plant superintendent, said it was unthinkable to vote for a dead person over a living candidate with a long record like Mr Ashcroft.

"I'm sure Jean Carnahan is a great lady, but that vote for her late husband doesn't make any sense."

Missouri is a key state for the Democrats, who need a net gain of just five seats in next month's election to take the Senate. It is one of seven states, out of the 34 up for election, where a Democrat gain is a real possibility.

Mr Ashcroft and Mr Carnahan had been rivals for 20 years and this campaign had often become bitter and personal.

Three widows of congressmen are currently members of the U.S. House - Mary Bono, a Republican, and Lois Capps, a Democrat, both from California, and Jo Ann Emerson, a Missouri Republican.

All three first won special elections to succeed their husbands, and all three won re-election in 1998.