1 in 4 adults to wager on NCAA tournament, survey reveals

Millions of brackets will be filled out, then busted, and billions of dollars will be bet on one of America's favorite wagering events -- the NCAA men's basketball tournament.

In the first 14 hours after the field was set Sunday night, roughly 2,600 brackets per minute -- totaling 2.2 million -- were created in the ESPN Tournament Challenge. Overall, when the Round of 64 tips off Thursday, an estimated 56.3 million American adults could be battling it out in bracket pools, according to survey results released by the American Gaming Association.

Even more will have money on the line.

The AGA survey results suggest $15.5 billion will be bet on the men's tournament, with one of four American adults (68 million) having money at stake on March Madness. The AGA's estimate of amount wagered includes bets placed with a sportsbook, casually among friends or part of a bracket contest.

"March Madness is one of the best traditions in American sports and America's most wagered-on competition," AGA president and CEO Bill Miller said in announcing the annual survey results.

The survey was conducted March 1-3 by data firm Morning Consult on behalf of the AGA, using a national sample of 2,200 adults.

Thirty-three states offer legal sports betting markets, including Kansas, Massachusetts and Ohio, which have launched since last year's NCAA tournament, and, Las Vegas will host a men's regional for the first time this year.