Bettors could pour more than $20 billion in wagers on NFL and college football games into legal U.S. sportsbooks during the 2021 season, resulting in as much as $1.5 billion in revenue for those sportsbooks, according to projections by PlayUSA, which tracks the regulated sports betting market in the U.S. Significant variables such as when a slew of new markets launch later this year make a precise prediction difficult, but the football-related handle in 2021 could triple the estimated $7.5 billion bet on football during the 2020 season.