TRADING POLITICAL EVENTS
Plain English
Politics is the most popular PM category — and the most prone to ideological bias. The trader who can stay objective and use polling models has a significant edge over wishful thinking.
Going deeper
Polling-based models (FiveThirtyEight, Decision Desk HQ, Silver Bulletin) typically lead PM prices by 2-3 days during election cycles. Read the model's methodology — house effects, sample weighting, fundamentals adjustments — to understand its biases. Layer in special-event factors: debate impact, primary calendar, vice-presidential picks. The most consistent edge comes from contracts mispriced by partisan retail traders: Republican retail over-prices Republican wins; Democratic retail over-prices Democratic wins. Fading these biases on contested races is a known PM strategy.
Examples
Polling lag arbitrage
A new high-quality poll moves the FiveThirtyEight model from 55% to 62% Democratic. PM markets often take 24-72 hours to fully reprice. Position into the gap.
Fading partisan bias
On the night of the 2020 election, Polymarket showed Trump at 80% Yes during early returns. Calibrated models had it much lower. Traders who faded the partisan momentum profited on the eventual reversal.