Senate odds face scrutiny as Asian stocks slip before midterms

Asian stocks edged lower as trading began on Tuesday, while oil prices stabilised after tumbling in the previous session, according to Reuters. Investors were uneasy ahead of US midterm voting.

Senate control draws market attention

In its Nov 3, 2026 reporting, published at 3:15 AM ET, Reuters noted that Polymarket and Kalshi were assigning around 75 percent probability to Democrats controlling the Senate.

Those readings put Democratic Senate control as the more likely outcome on both prediction-market platforms, but still leave room for a different result. The reported probabilities are expectations, not election outcomes.

Political surprises remain a risk

MUFG analysts pointed to the Brazil election surprise as a reminder that prediction markets can misprice political tail risks, according to Reuters. Their warning highlights the uncertainty that remains even when market pricing clearly favours one outcome.

The early moves in Asian stocks and oil provide a backdrop to the voting. They do not, on their own, establish whether the Senate probabilities are well calibrated.

What it means for prediction markets

• A clear favourite, not certainty: Around 75 percent odds on Polymarket and Kalshi favour Democratic Senate control without ruling out an alternative outcome.
• Tail-risk pricing is in focus: MUFG’s Brazil comparison cautions against treating a strong market consensus as protection from political surprises.
• Timing matters: The probabilities reflect the snapshot in Reuters’ Nov 3, 2026 report, rather than a final assessment of the election.