Duke Leads March Madness Market as Kalshi Shows Wide Open Title Race

According to prediction market operator Kalshi, Duke is the highest-priced favorite for the 2026 NCAA Tournament. However, the general consensus is that the tournament is a close call. Duke has a 21% chance of winning, making them the favorite but not the front-runner. 

Arizona and Michigan trail closely at 18% each, keeping the gap at the top narrow. Florida is next at 11%, and no other team reaches double digits. After that, the numbers thin out quickly, with most programs sitting in the low single digits or below 1%. Only 16 teams clear the 1% mark, which shows how quickly confidence drops off beyond the main group. 

All 68 teams are priced by Kalshi, one of the best prediction markets, including the weaker teams at the bottom of the bracket. Yet all of these teams are given fractional chances by the platform. Still, the structure itself indicates that only a small number of the teams are considered potential winners. 

This tight pack at the top shows there is not much separation between these teams. Duke is ahead, but Arizona and Michigan are within striking distance, and Florida is still within reach. Then, there is a big drop-off. 

Historical trends help explain that distribution. Teams that combine efficient offense and defense, experienced rotations, and depth tend to perform better over multiple rounds. Programs with a track record in the tournament often stay near the top of projections for that reason. 

Even so, the format leaves room for disruption. Lower-seeded teams still break through most years, which keeps overall probabilities compressed and prevents any one team from standing too far apart. 

Betting growth and advertising shift

Interest in March Madness continues to expand beyond brackets and into regulated wagering. The American Gaming Association (AGA) estimates that $3.3 billion will be legally wagered on the men’s and women’s tournaments this year, a 54% increase over the past three years. 

At the same time, sports betting advertising patterns are shifting. Data compiled by the AGA shows that traditional sportsbook visibility has declined, while prediction market platforms are gaining ground. Digital sportsbook ad impressions dropped nearly 14% in 2025, while prediction market advertising climbed. 

Kalshi has become a major presence in that space. It ranked as the third-largest sports betting advertiser by digital impressions in 2025 and now leads the category in early 2026 with about 5.2 billion impressions. FanDuel follows at roughly 2.9 billion. 

Such growth is also raising some concerns about compliance. Approximately 43% of digital sports betting advertisements seen in early 2026 failed to include required responsible gaming messages, particularly among prediction market operators.  

Sportsbook ad spend decreased by 5% year over year, further extending a trend of overall decrease even as betting continues to grow.