SimpleFunctions
Winner-take-all · 3 outcomes3 contractsPolymarketrefreshed 3 min agoCloses Sep 1, 2026 · 115d

MA-08 Democratic Primary Winner

Leader sits at 51% across 3 bound outcomes, runner-up at 42%. This is a winner-take-all market — the headline is the leader’s price, not an arithmetic mean.

Leader probability

51%

Stephen Lynch

runner-up 42¢leader 51¢

Outcomes

3

winner-take-all

Runner-up

42¢

Patrick Roath

Spread

9pp

contested

24h volume

$27

thin orderbook

Closes

Sep 1, 2026

115 days

Venue

Polymarket

3 bound

30-day trend

0%50%100%-30d-3w-2w-1wtodayStephen Lynch: 47% (28 days, 28 points)Stephen Lynch: 47% on 2026-05-08Patrick Roath: 39% (28 days, 28 points)Patrick Roath: 39% on 2026-05-08Andrew Zylberfink: 9% (28 days, 27 points)Andrew Zylberfink: 9% on 2026-05-08
Stephen Lynch47¢Patrick Roath39¢Andrew Zylberfink9¢
Top 3 candidates by current price · 28d

Bracket family

How the bracket ladder is priced.

Each row is one outcome on the venue. Sorted by 24h volume — the heaviest book is at the top.

Analysis

This probability indicates the market's assessment that the leading candidate in Massachusetts's 8th congressional district Democratic primary has roughly a 48% chance of winning, with a strong challenger at 41%. The moderate gap between the top two contenders reflects meaningful uncertainty about the race outcome. Movements in this probability would likely respond to campaign funding data, endorsement announcements from party figures, or polling releases. The primary election date itself represents the ultimate resolution event that will determine the actual winner and settle all contracts. Until then, shifts in candidate visibility, organizational strength, and voter sentiment in the district will drive market reassessment of these probabilities.

  • Gap between leader (48%) and runner-up (41%) is 7 percentage points, indicating competitive race rather than clear frontrunner
  • Polymarket volume across three contracts ($816 in 24-hour trading) provides moderate liquidity but limited depth for high-confidence price discovery
  • Massachusetts primary election date will serve as hard resolution point for all contracts
  • Candidate fundraising reports and endorsements from state/federal Democratic figures would provide concrete data to shift probabilities
  • Polling data or turnout metrics specific to MA-08 district would offer measurable input for market repricing

What moved the line

  • May 6Stephen Lynch26pp4672¢ · Polymarket
  • May 8Stephen Lynch14pp6147¢ · Polymarket
  • May 7Stephen Lynch11pp7261¢ · Polymarket
  • May 6Patrick Roath11pp4736¢ · Polymarket
  • May 8Patrick Roath8pp3139¢ · Polymarket

Recently closed in election 2026

These markets stopped trading. Last odds and any captured outcome are shown above — full settlement detail lives at the venue.

More like this

Other questions in election 2026.

How we compute these odds

SimpleFunctions aggregates live prediction-market contracts from Kalshi and Polymarket. Each slug groups contracts that resolve on the same underlying event, identified by venue event_id.

For binary slugs, the headline probability is the liquidity-weighted mid-price across all bound contracts. For multi-outcome slugs (e.g. elections with 3+ candidates), the headline is the leader’s price; we never arithmetically average disjoint outcomes — that would produce a number with no real-world meaning.

Snapshots refresh every 5 minutes during market hours; daily aggregates are computed at 04:00 UTC. The 30-day sparkline is drawn from per-ticker daily means stored in market_indicator_daily; 24h delta and movement events are derived from the same source.

Last updated on this page: 3 min ago.