It will be up to the Utah Democratic Party to nominate a replacement senator, he said. The party will forward names to Gov. Jon Huntsman Jr. to choose from.

"We're all hoping ... that the party will recognize the important contributions his wife has made, Karen, and will consider her as a possible nominee," Valentine said.

Although it's the statutory responsibility of the Democratic Party to name possible replacements and he is a Republican, Valentine said he personally hopes the Democrats will consider Karen Mayne because "she would make a great senator."

Senate Minority Leader Mike Dmitrich, D-Price, said the Democratic Central Committee will send a recommendation to Huntsman for a replacement.

"The governor then makes the final appointment," he said. "It'll probably be his wife, I'm just guessing."

Dmitrich said Sen. Mayne was a true fighter, battling for senior citizens, to provide eyeglasses and dental care for the disadvantaged, for a boost in the minimum wage. "Ed was the most compassionate and toughest individual I've ever known," he said. "He had that mean approach, but he was very mild and well-mannered. And he always looked out for the less fortunate people in our society."

He fought endlessly for those people, he said. At the same time, Dmitrich added, Sen. Mayne was a loving person. "His love for animals and human beings was unsurpassed by anybody."

Once a new senator is appointed, leaders of Senate Democrats will hold a meeting to choose a new assistant minority whip.

Senate Minority Whip Gene Davis, D-Salt Lake, said Senate Democrats "are very saddened by his loss. We looked to Ed's leadership and his concerns. He was always a champion of the people."

Davis said Sen. Mayne not only talked about working men and women, he lived his life working "to improve their well-being, whether it be minimum wage battles, whether it be battles for folks who live in some of the trailer parks in town, whether it be those who may be hurt by the payday loan companies."

Sen. Mayne was always there championing those causes, Davis said, and he "truly represented his district."

His death is a major loss to the people whose causes he espoused and to the state of Utah, he said.

Reporters who covered the Legislature recalled Sen. Mayne taking DVDs like the movie "Babe" to legislative session's final days, and playing them on his computer with the screen turned to allow those in the press gallery to watch, too.

He always maintained a good sense of humor on the floor, even when disagreements arose, observers said. A fund-raiser for Mayne that was scheduled earlier will still be held on Dec. 4, said Randy Horiuchi, a member of the Salt Lake County Council. Planned for the Grand America Hotel, its speakers will include Sen. Orrin Hatch, R-Utah, he said.