Will Maura Sullivan be the Democratic nominee for NH-01?

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TradingContract settles 8 Sept 2026Last checked 7 Sept 2026, 23:55 UTC

Data may be delayed. These prices have not refreshed recently, so treat them as a last known reading rather than a current quote.

Bid/ask midpoint · retrieved 2026-09-07T23:55:28.141Z. Venue quote-update time is unavailable. Readings can be asynchronous.

82.5%bid 82.0% / ask 83.0%24h volume $19K · liquidity $34Kas of 7 Sept, 23:55 UTC · not refreshed recentlyView on Polymarket

Crossbook forecast

57.0%against a market price of 82.5% at the timeNO

Logged 5 Sept 2026, 04:31 UTC · Brier 0.3249

The clearest signal is the late polling sequence: Sullivan leads Shaheen by 2, 5, and 6 points across three August polls, with the latest fielded Aug. 28-31 giving her 33%-27%.
Sullivan's roughly $3.6M-to-$2.4M fundraising advantage and rise from 8% in Dec/Jan to front-runner status are positive signal, though the old poll is mostly stale.
Shaheen has meaningful counter-signal: Hassan, Kelly, Lynch, and most labor unions suggest strong in-state institutional support that can matter in a low-turnout primary.
Key risks keep this below two-thirds: high undecideds in UNH, Beriont's late rise and Howard's endorsement could reorder late deciders, and attacks over out-of-state/AIPAC-linked money are salient in NH.
With only three days to the Sept. 8 primary, there is little time for fundamentals to change, but late-breaking negative coverage or turnout effects can still move a plurality race.

What would change it: A final weekend poll or late decider break showing Shaheen ahead by several points, or Beriont surging into the high teens, would make Sullivan clearly less likely than not to win.

Settlement source

-25.5 probability points from the market at generation · med confidence · Polymarket

Base rate: In crowded open-seat U.S. House primaries, the final-week polling leader with a money edge wins more often than not, but leads inside or near the margin with many undecideds are far from safe.

Chosen by hand.

Settlement

Every answer this call has been given, oldest first. Nothing is edited: a correction is a new entry beside the one it replaces.

NOsettled 11 Sept 2026, 04:08 UTC · recorded 11 Sept 2026, 04:08 UTC · entered by handsettlement

What this call was reading

A Saint Anselm College Survey Center poll conducted August 17-18, 2026 showed Maura Sullivan leading Stefany Shaheen 26% to 24%, a statistical dead heat within the 5.2-point margin of error. as of 2026-08-20 · anselm.edu · within 90 days of this call
A University of New Hampshire Survey Center poll released August 26, 2026 showed Sullivan and Shaheen statistically tied at 24% and 19% respectively, with Carleigh Beriont at 11%, Heath Howard at 10%, and 29% undecided. as of 2026-08-26 · scholars.unh.edu · within 90 days of this call
A Tavern Research poll conducted August 28-31, 2026 showed Sullivan leading Shaheen 33% to 27%, with Beriont at 12%, Urrutia at 4%, and Howard at 2%. as of 2026-08-31 · oddsshopper.com · within 90 days of this call
Sullivan led Shaheen by 8 points overall in December/January UNH data with Shaheen at 33% and Sullivan at 8%, meaning Sullivan gained substantial ground over the course of 2026. as of 2026-01-22 · bostonglobe.com
Maura Sullivan has raised approximately $3.6 million for her campaign, while Stefany Shaheen has raised approximately $2.4 million, as reported in early September 2026. as of 2026-09-04 · nhpr.org · within 90 days of this call
Shaheen has been endorsed by Senator Maggie Hassan (August 26, 2026) and Senator Mark Kelly (August 11, 2026), along with former Governor John Lynch and most of the state's labor unions. as of 2026-08-26 · oddsshopper.com · within 90 days of this call
State Rep. Heath Howard suspended his campaign and endorsed progressive candidate Carleigh Beriont after the August 20, 2026 Saint Anselm poll was released. as of 2026-08-24 · bostonglobe.com · within 90 days of this call
Sullivan's campaign has faced attacks over receiving a large share of donations from outside New Hampshire, including AIPAC-linked donors, with Shaheen stating in a debate that Sullivan raised more than 90% of her campaign money from out of state. as of 2026-09-04 · nhpr.org · within 90 days of this call
Progressive candidate Carleigh Beriont gained momentum in the final weeks before the primary, rising from 3% in June to 12% in the August 20 Saint Anselm poll and 11% in the August 26 UNH poll. as of 2026-08-30 · bostonglobe.com · within 90 days of this call
Maura Sullivan is one of nine candidates running in the Democratic primary for New Hampshire's 1st Congressional District, scheduled for September 8, 2026. as of 2026-08-18 · news.ballotpedia.org · within 90 days of this call

Context

Polymarket prices this at 82.5%. No verified equivalent is currently listed on the other venue, so there is no cross venue comparison on this page.

Volume over the last 24 hours is modest, at about $18,808 on the busier venue. It closes today, so short term moves may say more about the settlement mechanics than about the underlying question.

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