Maine Democratic Senate nominee on July 27?

Platform comparison

Market context

The underlying event is whether Graham Platner, the Maine Democratic nominee for the 2026 U.S. Senate race, voluntarily withdraws before the statutory deadline of 5:00 p.m. ET on July 13, triggering the party’s ability to appoint a replacement by July 27. Platner has faced sexual assault allegations he denies, and key allies are pulling endorsements, yet no Maine political party has ever replaced its nominee in an election before[1]. This historical precedent makes the current 1 % crowd-implied probability on a replacement plausible, as the mechanism remains untested and the party’s inertia likely favours retaining Platner unless he exits decisively[1][2].

Traders should monitor formal announcements from the Maine Democratic Party, particularly the state convention scheduled to nominate a replacement candidate, and any shift in Platner’s public stance on remaining in the race[1][2]. The party voted on July 8 to hold this convention, indicating readiness to act if Platner withdraws, but the new nominee must still be declared by July 27[1]. Recent reporting from TIME confirms that pressure is mounting on Platner as allies withdraw support, suggesting the window for a credible withdrawal remains open until the deadline[2]. Divergence exists between prediction-market odds (1 % YES) and analyst consensus, which leans toward Platner staying unless forced out, while sportsbook lines on related Senate outcomes show no explicit pricing for a nominee change, highlighting a gap in market coverage[2][6].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to PolyGram, which mirrors the Polymarket order book directly.

Resolution & payout

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FAQ

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.