The full scale of betting on the NCAA men’s basketball tournament in the new post-PASPA era has been estimated by the American Gaming Association (AGA) to stand at $8.5bn this year. According to fresh research commissioned by the association, March Madness will see one in five adults placing a bet on the wildly popular tournament.

Key findings from the survey, conducted by Morning Consult, predict that 47 million American adults will contribute to that overall $8.5bn total, with $4.6bn wagered on a collective 149 million brackets by more than 40 million people. Nearly 18 million people will wager $3.9bn at a sportsbook, online, with a bookie or with a friend.

A further breakdown of those figures revealed that 4.1 million will place a bet at a casino sportsbook or using a legal app; 2.4 million will bet illegally with a bookie; and 5.2 million will bet online, most likely via illegal offshore sites.

The plurality of bettors favors Duke (29%) to win, followed by Gonzaga (9%), North Carolina (8%), Kentucky (7%), Virginia (5%) and Michigan (5%).

“During this year’s tournament – the first in post-PASPA America – sports fans are expected to bet 40% more than they did on this year’s Super Bowl,” said Bill Miller, AGA’s president and chief executive officer. “Unlike any other sporting event in the country, March Madness attracts millions who fill out brackets, make casual bets with friends or wager at a legal sportsbook, which Americans can now do more than ever before.”

Since the US Supreme Court’s ruling in May 2018, more than $5.9bn has been wagered in the now-eight states with legal, regulated sports betting, enabling consumer protections and generating valuable tax revenue for state, local and tribal governments across the country.

“These results indicate there’s still work to do to eradicate the vast illegal sports betting market in this country, and we’re committed to ensuring sound policies are in place to protect consumers, like the 47 million Americans who will bet on March Madness,” continued Miller.