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Ed Markey, ≥20%
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Ed Markey, ≥20% - Kalshi
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Vol.
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Resolved Sep 9, 2026
Latest in Elections
Closed: Sep 9, 6:49 PM EST
Kalshi
Description
The 2026 Massachusetts Democratic Senate primary will determine which candidate wins the party's nomination for the U.S. Senate seat. This event tracks the margin of victory—the difference in vote share or raw votes between the winner and the runner-up—to categorize the competitiveness of the race.
Kalshi
The margin of victory is calculated as the vote differential between the leading candidate and their nearest competitor. If a candidate wins, the margin equals their votes minus the second-place finisher's votes; if they lose, it equals their votes minus the first-place finisher's votes. A tie for first place results in a margin of zero. Margins are computed without rounding and can be expressed in percentage points, raw vote counts, or electoral votes as applicable. If a candidate appears on the ballot under multiple party affiliations, all votes for that candidate are aggregated. For uncontested races where a candidate runs unopposed, the margin is set at 100 percentage points or the total votes cast. Positive margins indicate a winning candidate; negative margins indicate a losing candidate. Each margin range is inclusive of its lower bound and exclusive of its upper bound—for example, a margin of exactly 6% falls into the 6-8% range, not the 4-6% range.
Frequently asked questions
Prediction markets and traditional polls often diverge because they measure different things. Polls capture voter sentiment at a single moment, while prediction markets aggregate real-money bets from traders who have financial incentives to forecast accurately. This market reflects traders' beliefs about the actual margin outcome, which may differ from the latest poll numbers if traders believe polls are outdated, biased, or missing late-breaking developments. Comparing this market's odds to published polling averages can reveal where the prediction market community sees an edge or disagrees with conventional wisdom.
On Kalshi, this market is priced through an order-book mechanism where traders buy and sell contracts tied to specific margin outcomes. On Kalshi, prices reflect that venue's order book, liquidity, and how traders price the outcome right now. Each contract represents a bet on whether the primary margin will fall within a defined range, and the price of each contract reflects the collective probability assigned by active traders. As new information emerges—polling updates, candidate announcements, or campaign developments—traders adjust their positions, moving prices in real time. Higher prices indicate stronger trader conviction that a particular margin outcome will occur.
This market resolves around Sep 1, 2027, once the Massachusetts Democratic Senate primary election has taken place and results are finalized. The outcome is determined by the official margin of victory between the top two Democratic candidates, verified against credible public reporting of the election results. Traders' positions settle based on which margin outcome actually occurs, making accuracy in forecasting the final spread the key to profitability in this market.
Several catalysts can shift odds in this market. Major polling releases showing movement in candidate support will likely trigger repricing, as traders update their margin forecasts. Candidate endorsements, debate performances, or campaign spending announcements may signal shifting momentum. Media coverage of gaffes, policy positions, or voter turnout expectations can also move prices. Demographic shifts in early voting or absentee ballot returns, if reported before election day, could prompt traders to adjust their margin predictions. Finally, unexpected candidate withdrawals or last-minute campaign developments could create sharp price movements as traders reassess the likely outcome.
