In the U.S., football is also number one, but in its American version. There is one significant difference in US sports betting as compared to the rest of the world in that football (aka soccer) is actually the number one sport for bettors in all other locations. Most Popular Sports to Bet on in the U.S. If there’s some type of contest, there’s probably a way to place a bet on it. Today’s sportsbooks take bets on the winner of the coin flip or the presidential election or even who will win a reality show competition. Today’s online betting sites allow for betting on pretty much any sport you can think of and sports betting doesn’t even need to, technically, be in conjunction with an actual athletic competition.