Since news of the allegations broke, Wallace says that former fraternity brothers have been calling each other, many expressing disbelief.

"If they did something wrong, this is the first time they did something wrong with their lives," Wallace said. "They shouldn't be crucified. They didn't hurt anyone."

Pyne says that the easygoing Harn didn't have the temperament - or stupidity - to engage in a fraud on this scale.

After college, Davis got married and set up a computer business in Baltimore. State incorporation records list him as president of Utopian Networks Inc., which a friend said provides computer network support for small- and medium-sized companies that don't have their own computer staffs.

In November 1997, Davis bought a house in the 300 block of South Collington Avenue, land records show. His wife, Cara Cameron, answered the door at the house last week. She said she and Davis separated in January and that she plans to file for divorce in a few months. She provided a brief written statement, saying:

"To the best of my knowledge, I am not now nor have I ever been a subject of this investigation. I will continue to cooperate with the FBI and other investigating authorities but will have no further comment."

Records show DaSilva moved to New York after leaving Drexel. One of his attorneys, Rae Downes Koshetz, said he is a "consultant" and is unmarried. The New York Times reported that a Web site for DaSilva Digital - described as a "provider of creative technology-enabled business solutions" - was taken down earlier this month.

After college, Harn landed a job as a programmer in Delaware at the Newark headquarters of Autotote, the top operator of computerized "totalisator" systems that record bets and calculate odds.

Harn met and married a woman from Peru while on a business trip, and briefly took a job at a competitor, International Lottery and Totalizator System Inc., of Carlsbad, Calif., according to Jim Snow, a spokesman for that company.

"We were going to send him to work on a customer site out of the country but he had a new wife and they didn't want to go to Europe," Snow recalled.

Harn instead returned to Autotote as a senior computer programmer in Newark. Two years ago, he and his wife had a baby.

This year, Harn was one of about a dozen software engineers in Newark, according to a co-worker who asked not to be named because Autotote told employees not to speak to the media. One of his tasks was upgrading Autotote's system to allow people to place bets over the phone without going through a clerk. Bettors set up accounts, deposit money and bet by touch-tone phone.

Luck or help?

Just how and when Harn's two friends became involved in betting on horse races is unclear.

Donald Groth, president of a telephone betting service in upstate New York, said Davis told him he was a regular at Laurel Park and Pimlico Race Course. There is no record of him ever filing a tax form, required if he had won more than $600, said Louis J. Raffetto, chief operating officer for the tracks.

On Oct. 18, Davis faxed an account application, which he had downloaded from the Internet, to Groth's company, Catskill Off-Track Betting Corp., a corporation set up by the state and controlled by the counties in the Catskill region. DaSilva had done the same thing on Oct. 3, according to police.

Depending on whom you believe, the men had remarkable luck - or help from a friend on the inside.

On the same day he established his account at Catskill, DaSilva won $1,757 by picking in advance the winners of four consecutive races run at Balmoral Park, a harness track near Chicago. Two days later, he hit a Pick Six, selecting the winners of six races run at Belmont Park in New York. The payoff: $107,608.

But that was chump change compared with what his Baltimore friend would soon win. On Oct. 26, Davis used his Catskill account for the first time to make a series of Pick Six bets on one of the biggest days in racing, the Breeders' Cup. That series of races is called the World Thoroughbred Championships and attracts the fleetest horses.

Multi-race strategy