"Considering the obstacles Colorado's market has had to face since it launched in May, the results so far have surpassed the expectations of all but the most optimistic," said Dustin Gouker, lead analyst for the PlayColorado.com. "Colorado is already in a small group of major U.S. sports betting markets, and it has reached that level long before the market has matured."

With a busy schedule of baseball, NBA, and NHL games throughout August, online and retail sportsbooks combined to generate $128.6 million in wagers, up 117% from $59.2 million in July, according to official data released Wednesday. The wagers over the 31 days of August netted $1.9 million in betting proceeds, down 22% from $2.4 million in July. The drop in net proceeds came in spite of a rise in gross revenue to $7.5 million from $5.2 million, the result of increased marketing.

August's wagers produced $189,462 in state taxes and topped the $122.9 million in bets that sportsbooks generated over the industry's first three months combined.

Colorado sports fans had plenty of motivation in August. Fueled by the Denver Nuggets, basketball was the main driver in August, attracting $38 million in bets. And baseball generated another $22.8 million in bets. With the Colorado Avalanche enjoying a playoff run of their own through August, hockey drew another $13.6 million in wagers.

With the Nuggets in the Western Conference Finals and the Denver Broncos season under way, Colorado's monthly record will likely be short-lived.

"As impressive as August was, September will almost certainly be even better with the Nuggets and Broncos in play," said Jessica Welman, analyst for PlayColorado.com. "With table tennis as the state's top draw in the first few months, it was impossible to get a reliable read on Colorado's market. We now know it's a market that responds well to its home teams. After September, though, we will find out how much interest in sports betting is driven locally as the Nuggets season wanes and if the Broncos continue to struggle."

Perhaps most surprising is Colorado's push toward the nation's fourth largest market, Indiana, which attracted $169 million in bets in August. The Hoosier State has a more mature market, a larger population than Colorado, and is boosted by relatively large markets — including Chicago, Cincinnati, and Louisville — just across its borders.

The Centennial State has its own advantages, though, including its ability to entice sportsbook operators with an attractive regulatory framework and heavy interest in Denver-area professional sports teams. Just recently, TheScore Bet and the first U.S. sportsbook from European bookmaker SportsBetting.com have launched in Colorado, with even more to follow.

"Colorado started as a relatively open market for sportsbook operators and a well-conceived regulatory framework have made the state especially appealing," Gouker said. "With multiple bookmakers who have never operated in the U.S. before, Colorado is beginning to look like no other market in the U.S."