2023 was a year of firsts for bettors in the United States.

For the first time since legal betting began expanding around the nation in 2018, bettors in the United States wagered more than $100 billion with American sportsbooks. Bettors also lost more than ever, a net $9 billion and counting in 2023, according state-by-state revenue reports compiled by gambling industry reporter Chris Altruda.

The $9 billion figure is comparable to how much Americans are believed to spend on unwanted gifts annually, by the way.

Thirty-seven states and the District of Columbia offered legal betting in 2023. New York boasted the largest betting market, with more than $17 billion bet on the year, significantly more than any other state. New Jersey and Illinois are second and third in terms of amount wagered, while any predicted demise of Nevada's sports betting market has not materialized. Nevada is on pace to eclipse $8 billion in sports bets for the second straight year, nearly double the amount the state's books handled in 2017, the year before sports betting began expanding around the nation.

Parlays, including the increasingly popular same-game parlays (SGPs), have increased win rates for sportsbooks. For decades, when Nevada was primarily the only state with regulated betting, the win rate for sportsbooks hovered between 5 and 6%. Now, thanks to the growth in parlay betting, states are regularly reporting win rates of 8 and 9% or higher. Through November in New Jersey, more than $2.5 billion had been wagered on parlays with the state's sportsbooks. The books won a net $486.1 million on parlay months during that stretch, for a cushy 18.9-win percentage.

Maybe things will turn around for the betting public in 2024, although the odds are against it. In the meantime, here's a look back some of the wildest wins and dumbfounding betting loses from 2023.

Notable bets of 2023

• The Los Angeles Chargers jumped out to a 27-0 lead over the Jacksonville Jaguars in a wild-card playoff game last January. At that point, DraftKings was offering the Chargers' odds to win the game at -12,500, meaning a bettor would need to risk $12,500 on the Chargers to win $100. An unidentified bettor took it a few steps further, risking $1.4 million on the Chargers to try to win $11,200. The Jaguars would rally back for a 31-30 win, the third-largest comeback in NFL playoff history, and the bettor would lose $1.4 million.

• On April 3, two days before the NFL draft, the odds on Kentucky quarterback Will Levis to be the No. 1 pick moved from 40-1 to 4-1, after an anonymous post on Reddit claimed Levis was "telling friends and family Carolina will in fact take him on Thursday."

Bryce Young would go No. 1 to the Carolina Panthers, and Levis would not be drafted until the second round.

• In Week 2 of the NFL season, FanDuel paid out more than $20 million on a prop bet based on field goals. The sportsbook offered 200-1 odds that every team in the 12-game Sunday afternoon slate would make a field goal. FanDuel said more than 21,000 bets were placed on the prop, at an average of $6 per wager. Only once in the last 20 seasons had every team in the afternoon games made at least one field goals.

• FanDuel reported taking a 25-cent, 21-leg NBA parlay that hit at odds of +45502208 and won $113,755.57.

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• The Purdue Boilermakers became the second No. 1 seed in history to lose to a No. 16 seed in the NCAA men's basketball tournament last March. The Boilermakers lost outright to the Fairleigh Dickinson Knights as 23.5-point favorites. It cost a veteran Las Vegas bettor upward of six figures, while he tried to win just a couple thousand.

• A bettor at BETMGM correctly picked the point spread winner for the first 14 games of the NFL season in a $10 parlay with +873495 odds paid $87,349.50.

• Florida's wild return to the American betting market included one of the largest parlay payouts ever reported -- $6 million -- and one of the largest single bets ever reported on a midweek MAC game: $1.5 million on a one-win Kent State team.

• On Dec. 29, with four long shot parlays down to their final legs, a bettor with ESPN BET needed favored Ohio State to beat Missouri in the Cotton Bowl. The bettor wasn't willing to stick with the Buckeyes and chose to take the sportsbook's cashout offer of $41,066.76 on his $16 in parlays. Ohio State would lose to Missouri.

$16 ➡️ 41,066.76An early cash-out ahead of Ohio State's loss to Missouri helped this bettor win FOUR different college football and basketball parlays. 😱ABSOLUTELY WILD. 🤯 pic.twitter.com/YYRAL8nTZV— ESPN BET () December 30, 2023

• On Dec. 24 and Dec. 25, two bettors hit a pair of 14-leg NFL touchdown-scorer parlays with low stakes and massive odds at ESPN BET.

First a bettor hit a $2, 14-leg parlay that, at +2992511 odds, paid $59,852.22, when DK Metcalf, Geno Smith, Mike Evans, Rachaad White, Justin Jefferson, Jahmyr Gibbs, Amari Cooper, David Njoku, Romeo Doubs, Derrick Henry, Gardner Minshew, Case Keenum, CeeDee Lamb and Raheem Mostert each scored touchdowns in Week 14.

The bet would be topped the next day, when a New Jersey bettor with DraftKings hit a $5, 14-leg parlay that featured 14 NFL players to score touchdowns in their respective games that had 97,875.6-to-1 odds. The bet came down to San Francisco 49ers running back Christian McCaffrey finding the end zone against the Baltimore Ravens on Christmas night. McCaffery delivered, scoring on a 9-yard run in the second quarter, and the bettor received a $489,383.01 stocking stuffer from his $5 bet. The odds were the longest on a winning bet reported by DraftKings in 2023, with a caveat below.

• A New Jersey bettor, who is part of DraftKings' VIP program, shared a screenshot of a $1, six-leg parlay that featured the exact results for six fights at UFC 285 at +3997171 odds. (DraftKings' policy is not to publicize bets from a VIP without approval). The bettor won $399,472.71, and DraftKings confirmed the legitimacy of the bet to ESPN.

I hit earlier this year from NJ and at bigger odds. 🤴 pic.twitter.com/IMR7sMkgX9— Andrew Collins () December 27, 2023

• A $2,000 bet on San Francisco 49ers quarterback Brock Purdy to win MVP at 100-1 odds sold on online secondary market PropSwap for $125,000 on Dec. 22. Three days later, Purdy threw four interceptions in a blowout loss to the Baltimore Ravens, and Lamar Jackson emerged as the odds-on favorite to win the MVP. Purdy enters Week 18 as a 25-1 long shot.

• In early May, an Ohio bettor with online sportsbook Tipico bet $1.62 on a 17-leg parlay featuring an array of NBA and Major League Baseball props that hit at odds of +1821338. The bet paid $29,506.68.

• The Kansas City Chiefs were the most popular NFL team with bettors at Caesars Sportsbook and were also involved in the biggest decision on a single game of the regular season. When the Chiefs traveled to New York to take on the Jets in Week 4 on "Sunday Night Football," the betting public loaded up Kansas City as the favorite, with upward of 90% of the money on Kansas City to cover the spread. The ending saw Chiefs quarterback Patrick Mahomes elect to slide instead of scoring a touchdown that would've covered the spread and handed sportsbooks their biggest loss of the season.

• The NFL's dominance as America's favorite league to bet is reflected heavily by the teams that attracted the most bets and the most money wagered in 2023 at DraftKings. In terms of money bet, the top 10 teams in sports are from the NFL. In terms of the number of bets, the NFL boasts the top eight teams, with the Denver Nuggets and Boston Celtics coming at No. 9 and 10.