An estimated 23.2 million Americans plan to bet on Super Bowl LV, combining to risk potentially $4.3 billion -- an expected decrease of approximately 37% from last year, according to research by the American Gaming Association released Tuesday.

With the ongoing coronavirus pandemic, both figures are down from last year's estimates from the AGA, despite 36 million more Americans having access to legal sportsbooks in their state or jurisdiction. Similar research from the AGA last year estimated that 26 million Americans would combine to bet $6.8 billion on Super Bowl LIV.

The pandemic is expected to cut into the amount wagered at retail sportsbooks and reduce casual bets, such as office and squares pools that are made in social settings. Online betting on Sunday's matchup between the Kansas City Chiefs and Tampa Bay Buccaneers, however, could increase dramatically, the research showed, with a record 7.6 million Americans potentially placing wagers on mobile betting apps and websites, a 63% year-over-year increase.

The research is based on an online survey of 2,198 adults conducted last week by polling firm Morning Consult on behalf of the AGA.

Since last year's Super Bowl, seven more jurisdictions have launched legal sports betting markets: Colorado, Illinois, Michigan, Montana, Tennessee, Virginia and the District of Columbia. Legal sportsbooks are now operating in 20 states and the District of Columbia.

As Americans moved away from offshore and unregulated bookmakers, more than $21 billion was bet at U.S. sportsbooks in 2020, up from $13 billion in 2019. More than $210 million in state and local taxes was generated from the U.S. sports betting market in 2020, according to the AGA.

"This year's Super Bowl is expected to generate the largest, single-event legal handle in American sports betting history," Bill Miller, president and CEO of the American Gaming Association, said in a news release announcing the survey results. "With a robust legal market, Americans are abandoning illegal bookies and taking their action into the regulated marketplace in record numbers."

Las Vegas retail sportsbooks, typically packed on Super Bowl Sunday, are bracing for any potential decrease in in-person betting. An estimated 1.4 million Americans could bet in-person at sportsbooks this year, down 61% from 2020, the research found.

Less wagering in Nevada could be a net positive for bettors. Since 1991, when Nevada Gaming Control began tracking the betting results on the Super Bowl, the state's sportsbooks have suffered a net loss only twice (1995 Chargers-49ers and 2008 Giants-Patriots).

New Jersey sportsbooks haven't been as fortunate when it comes to the Super Bowl. Since the state launched a legal sports betting market in 2018, New Jersey sportsbooks have suffered a net loss on the past two Super Bowls.

Fifty-six percent of bettors in the AGA survey said they were planning to bet on the Chiefs, with 44% indicating they would be backing the underdog Buccaneers.