"We must restore civility to the public square,'' said Nelson, who served in the House of Representatives from 1979 to 1991. ``We need to come together in reconciliation instead of continuously being divided.''

In 1986, while a Democratic congressman representing Floridas Space Coast area, Nelson became the second member of NASAs politician-in-space program, following Senator Jake Garn, a Republican from Utah.

Nelson, center, and the crew of Space Shuttle Columbia.

Aboard flight STS-61C on the shuttle Columbia, Nelson was involved with a University of Alabama at Birmingham experiment that hoped to grow crystal proteins in outer space for cancer research and served as the subject for medical tests examining the effects of microgravity on the human body.

The space agency chose Nelson and Garn for slots on the shuttle missions because of their positions on key congressional panels that oversaw NASA. Nelson was the chairman of the House space subcommittee and Garn headed the Senate appropriations subcommittee that oversaw NASAs budget.

Nelson, who left Washington in 1992 to make a bid for the Florida governors mansion -- which failed -- already has become one of the few politicians to make space exploration an issue in the November elections.

Nelson's campaign centered on a September debate held near Cape Canaveral about space issues, but both the events sponsors and the McCollum campaign demurred, opting to focus on statewide issues.

In August, Nelson told Florida Today that he would make a piloted mission to Mars a legislative priority.

"In my lifetime, what I want to see is a mission from Planet Earth to Planet Mars with an international crew that returns safely," Nelson told the newspaper. "I think we can do that. We have the technology, we just have to have the will to do."

During his tenure in Congress, Nelson was an ardent advocate for NASA and space exploration. He was the prime sponsor on a bill that would fund construction of the shuttle Endeavour, NASAs replacement for the shuttle Challenger.

The Endeavour bill may have had some personal significance for Nelson -- his shuttle flight touched down just 10 days before the Challenger lifted off on its doomed mission.

Critics say, however, that as a congressman Nelson was too protective of the space agency, charging that he used his position as chair of the space subcommittee to act as a booster for NASA, instead of as an independent check on the agency.

Nelson and the space agencys other backers on the space committees were "NASAs biggest fans when you get right down to it," Donald E. Day, an auditor with the General Accounting Office, Congress investigative arm, told the New York Times in a 1986 article.