Midterm Senate odds slide across prediction markets

Democratic Senate probabilities retreat

Democratic prospects for Senate control and the Michigan Senate race weakened this week in DeFi Rate’s cross-platform prediction-market aggregation, according to the outlet’s summary published Oct 13, 2026, at 2:24 AM ET.

The aggregated probability of Democrats controlling the Senate fell from 65% to 62%, a decline of 3 percentage points. The move narrowed the party’s advantage, while leaving its probability above 50%.

For the Michigan Senate race, the Democratic probability dropped from 72% to 68%. DeFi Rate’s summary labels that decline as 5 percentage points, although the stated endpoints imply a 4-percentage-point change.

The available summary is truncated, and the underlying page text was unavailable. It therefore provides no basis for identifying the platforms behind the aggregation, explaining the moves or assessing whether other Senate races followed the same pattern.

What it means for prediction markets

• Both listed Democratic probabilities declined but remained above 50%; the moves indicate weaker expectations, not a reversal in the favored outcome.
• The Michigan figures contain a discrepancy between the reported change and the endpoints, limiting precision when comparing its move with Senate control.
• These are cross-platform aggregates. The available material does not show individual-market prices, trading volume or liquidity.