Congressional betting volume grows while study highlights easily moved prices

Congressional prediction markets have drawn more than $431 million in wagers, yet 96 percent could see their prices moved by five cents for $3,500 or less, according to Gambling Insider’s reporting on research from the Anti-Corruption Data Collective.

Heavy wagering, limited price resistance

The research, published November 2, examined 28,845 congressional markets across Kalshi, Polymarket and Polymarket US. Betting volumes were nearly triple those for the 2024 congressional elections, according to Gambling Insider.

The study also found that 66 percent of live markets could be moved by five cents for under $100. That finding places the cost of changing displayed prices alongside the much larger aggregate wagering figure.

Scrutiny of election signals

The distinction matters when market prices are presented as evidence of who is winning. Large betting volumes and the cost of moving an individual market’s price measure different things; the study’s findings raise transparency questions about how those signals are interpreted.

The reported research identifies how cheaply prices could be shifted, rather than establishing that such shifts occurred. For readers assessing congressional election markets, that is an important limit on what the figures show.

What it means for prediction markets

• Volume alone is not a measure of price resistance. More than $431 million wagered coexists with a finding that 96 percent of markets could move five cents for $3,500 or less.
• Live-market prices warrant context. The study found that 66 percent could move five cents for under $100, complicating their use as standalone evidence of electoral strength.
• Potential movement is not documented manipulation. The reported figures describe the cost of shifting prices, not proof that anyone acted to distort them.