LAS VEGAS (NewsNation) — March Madness is in full swing, with do-or-die match-ups; the second round tipped off Saturday.

The fear of choosing teams incorrectly hasn’t stopped millions from trying their hand at sports betting all across the U.S.

2022 is predicted to be a massive year for NCAA tournament betting. Since last year’s event, 29 million more Americans can legally wager in their home state.

The American Gaming Association predicts around 45 million people will bet on this year’s tournament, wagering $3.1 billion.

Sports betting is legal in more than 24 states in the U.S., though many have only in-person betting.

Aside from the in-person sportsbooks, sports betting websites are trying to reel in new customers by offering promotions. For example, FanDuel, one of the premier online sportsbooks in the U.S., offers $150 in free bets for anyone who has a $5 wager on any March Madness money line.

Bookmakers at Westgate Superbook, the largest sportsbook in Las Vegas, told NewsNation they face the difficult task of setting the betting lines and making it attractive for customers to come in and put their money down.

“And we just got to go with it, you know. Sometimes, we’re, most of the time, spot-on; and other times, we might be off maybe a couple here and there, but we have a lot of competence in our numbers,” one bookmaker said.

One of the more interesting shifts that can be seen across America is that fewer people are participating in those online bracket pools. Instead, as more states come online across America legalizing sports gaming, many bettors are attracted to the single-game action. That means betting on the spread, betting on the money line, and betting on some of those other single-game contests.