Superforecasters edge Polymarket in Senate forecast comparison, with Alaska unresolved

Good Judgment’s November 4 analysis found that Superforecasters performed better than Polymarket prices in a comparison covering 16 Senate races in 2026. The assessment used forecasts and market prices from November 2.

Alaska outcome affects the final scores

According to Good Judgment, Superforecasters recorded a Brier score of 0.086, compared with 0.101 for Polymarket. Lower scores indicate better performance on this measure.

Those figures depend on Mary Peltola winning in Alaska. They therefore represent a conditional assessment rather than a comparison independent of that race’s outcome.

If Dan Sullivan retains the seat, the Superforecasters’ score rises to 0.108 and Polymarket’s to 0.130, according to Good Judgment. Both perform worse under that scenario, but the gap between them grows.

What it means for prediction markets

• Superforecasters lead under either Alaska outcome presented in the analysis; the unresolved result changes the size of the advantage, not the ranking.
• The comparison evaluates November 2 forecasts and prices across 16 Senate races, rather than performance throughout the election cycle.
• Readers should distinguish the Peltola-dependent scores of 0.086 and 0.101 from the Sullivan-dependent scores of 0.108 and 0.130.