GAINESVILLE, FLA. -- Kerwin Bell doesn't drink, smoke, or swear. He married his grade school sweetheart, a drum majorette. Among the many legends that have grown up around this 22-year-old American football hero, is that at age 2, he asked for "a big ball," and that at 3, when his mother was teaching him to write, he replied, "Mama, I don't need to know how to write, I just need to know how to sign a contract."

When Kerwin Douglas Bell married Cosette Odom last year in Mayo, Fla., the bridesmaids wore orange and the ushers wore blue. That was for the University of Florida, of course -- the school that let him hold up the practice dummies as an eighth-stringer before anybody but him knew he was good at throwing a football, which, incidentally, is what he wrapped the garter around when he tossed it at the wedding.

Bell, now a Heisman Trophy candidate in his senior year at Florida after beginning as a walk-on, grew up nearly undiscovered on his father's 200-acre tobacco farm. He dreaded summers, because that meant Doyle Bell was going to put him to work in those fields, sunup to sundown, six days a week all summer long. School was better than curing tobacco, but Bell found even the latter preferable to the quiet sameness of Mayo, a town of slightly more than 800 in Lafayette County. Actually, it is the only town in Lafayette County, where Bell's high school, the only high school in the county, had just 202 students.

No athlete from Mayo-Lafayette High had ever received a scholarship to a Division I football program. And when Bell left, he didn't have one either, even though he led the school to a state championship his junior year. No coaches bothered to go all the way to Mayo to see him. So he drove to Florida, where he joined the scout team in 1983.

By the next year Bell worked his way up to fifth string, but just before the start of fall practice then-coach Charley Pell told Bell to prepare himself for another season on the scout team. However, then began a fateful number of position changes and eligibility and injury problems that wiped out four quarterbacks in the fall of 1984. Finally, starter Dale Dorminey got hit in the knee during a no-contact practice.

Pell had no one to turn to but the gawky player who had been denied a scholarship even by Valdosta State. When wide receiver Ricky Nattiel heard the news, he jogged over to the second team's huddle.

"Country," he said, "you better grow up fast."

Bell started that first game of the 1984 season, and promptly shocked the nation by scoring a touchdown to put the Gators ahead of Miami, 20-19, in a game they eventually lost, 32-20. He went on to lead the Gators to a 9-1-1 record, their best ever. He was named Southeastern Conference player of the year and became a Florida folk hero.

"Here was a chance I never thought I'd get," Bell said. "I figured it was my only chance, so I better do something."

He has thrown for a total of 6,467 yards for his career, fourth in SEC history, and climbing. Counting the Gators' 3-1 record so far this season, Bell has led Florida to a 27-8-2 mark. If the Gators, who play at Louisiana State Saturday, continue to have the sort of season that is expected, he will be one of those still in the Heisman Trophy race. No walk-on has ever won the award and only one Gator, Steve Spurrier, has ever won it.

"Something I never thought possible," Bell said of the Heisman.

Bell's Heisman hopes temporarily faded somewhat when the Gators lost their opener to Miami, 31-4, and he was sacked five times and threw three interceptions. He has since climbed slowly back in the race, completing 45 of 82 passes for 651 yards.

"I think his confidence was up with all the Heisman hype," said reserve quarterback Pepe Lescano, a walk-on also. "After Miami he was questioning himself. He might have been pressing a little, trying to prove who he is."

How much the Heisman really matters to Bell is hard to discern, buried under modesty. "It'd be nice to be the first walk-on to win it," he said. "But I haven't did anything yet." Even so, he has had country songs written about him ("The Throwin' Mayoan") and stuffed Kerwin dolls sold in his name.

"A lot of people have ability, and they're given all this attention, and they sort of get lazy," Bell said. "I've tried not to forget. I pull myself back."

Galen Hall, who took over when Pell was fired three games into the 1984 season, said of Bell, "Kerwin is sort of humble. He just likes to make people happy."

But beneath Bell's smile and general good will lurks the heart of an indomitable competitor. He has missed just two games in his career, both after spraining a ligament in his left knee last season. Still hobbled against Auburn, he came off the bench to score one touchdown, throw for another, and then score a game-winning two-point conversion.

In the state high school semifinals, Bell played even though he had been up the entire night before with a virus. Sometimes so woozy he did not remember going on and off the field, he led his team to victory anyway.

"He can't stand not playing," his mother, Zelda, said. "He's played when he was so sick he could hardly stand. Playing something was always a way of life to him."

Bell has nurtured his image as carefully as his career. He has worn No. 12 throughout his playing days in honor of Roger Staubach, whose 12-year-old son now has a poster of Bell over his bed. He is academically sound, majoring in psychology. He has a fixed smile and endless patience. He rarely says no to a request. This summer he did an extended speaking tour, even visiting a prison, where inmates baked a cake.

"That's the one thing I'm proudest of, my image," he said. "It don't seem like people even care about my football as much anymore, it's as a person. The main thing is that I'm respected by my peers. I'm proud of the way I live."