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Horizon · our Election Day forecast: polls, plus fundamentals like incumbency, fundraising and past results.

Pulse · polls only: where the races stand today, with no fundamentals and wider uncertainty.

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New Hampshire › U.S. Senate · November 3, 2026 · Updated Oct 16, 2026

U.S. Senate in New Hampshire

Pappas is clearly favored to win: Pappas wins in 19 of every 20 simulations.

Pappas (D)
94%
chance of winning
Sununu (R)
6%
Average margin
D+8.9
80% of outcomes
D+2 to D+16
Partisan lean
D+4
Polls
26in our database

Pappas is clearly favored to win: Pappas wins in 9 of every 10 simulations.

Pappas (D)
91%
chance of winning
Sununu (R)
9%
Average margin
D+7.9
80% of outcomes
D+1 to D+16
Partisan lean
D+4
Polls
26in our database

Range of outcomes

D+8.9R+20R+10EvenD+10D+20
D+7.9R+20R+10EvenD+10D+20

How the odds have moved

Chance of winning by forecast date.

0%25%50%75%100%AugSepOctNovNov 3Pappas 94%Sununu 6%

Updated nightly. Each day is the current model run on the polls that had ended by then (how).

0%25%50%75%100%AugSepOctNovNov 3Pappas 91%Sununu 9%

Updated nightly. Each day is the current model run on the polls that had ended by then (how).

The candidates

Democratic

Chris Pappas

U.S. representative for NH-1 (2019–present)

Experience
Statewide office or Congress
Raised
$15.4M
From individuals
$13.5M
Spent
$11.5M
Cash on hand
$4.3M

Money: FEC, through Aug 19, 2026.

Profile and career · Wikipedia

Republican

John E. Sununu

Former U.S. senator from this seat (2003–2009)

Experience
Statewide office or Congress
Raised
$5.3M
From individuals
$3M
Spent
$2.8M
Cash on hand
$2.5M

Money: FEC, through Sep 30, 2026.

Profile and career · Wikipedia

What goes into the forecast

Every ingredient's estimate of the final margin.

National environment
D+9.5Election Day forecast; federal races run in it
← RepublicanDemocratic →Lean + environmentUsual vote, shifted by the national and state moodD+11.7Fundamentals modelAdds incumbency, past results, money andexperienceD+13.2Polls in similar placesPolling of similar races in New Hampshire andlook-alike placesD+12.4Polling average26 polls, latest Oct 5D+7.6Horizon forecastPolls + fundamentals, projected to Election DayD+8.9Pulse forecastPolls (and polling of similar places) only, todayD+7.9

Each estimate is a margin before national and statewide uncertainty is simulated. Horizon blends polls, fundamentals and a little of the similar-places estimate, weighting each by how precise it is; Pulse uses polls and similar places only.

Fundamentals inputs
Incumbency (+1 D, −1 R)0
Fundraising edge (log ratio of individual money)1.5
Elected-experience edge0
First-term incumbent0
Seat's last result vs. expectation13.94
Incumbent's last result vs. expectation0

Polls

R+10R+5EvenD+5D+10Avg. D+7.6Sep 4Nov 3
All 26 polls
PollsterDatesSamplePappasSununuMarginAdjusted
YouGovSep 28–Oct 51,520 LV5143D+8D+7.1
Saint Anselm College for AARPSep 28–Sep 291,042 LV5144D+7D+6.9
Trafalgar GroupR-sponsoredSep 26–Sep 271,082 LV4741D+6D+8.2
New York Times/Siena UniversitySep 15–Sep 22613 LV5045D+5D+5.7
University of New HampshireSep 17–Sep 211,418 LV5042D+8D+9.0
InsiderAdvantageR-sponsoredSep 16–Sep 171,200 LV4840D+8D+10.5
co/efficientR-sponsoredSep 9–Sep 11958 LV4646Even
Rasmussen ReportsR-sponsoredSep 8–Sep 101,000 LV4534D+11
Fabrizio, Lee, & Associates for the NRSCR-sponsoredAug 27–Aug 30600 LV3637R+1
University of New HampshireAug 20–Aug 241,878 LV4345R+2
Saint Anselm CollegeAug 17–Aug 181,411 LV4841D+7
Peak Insights for the NRSCR-sponsoredJun 24–Jun 27500 LV4342D+1
Saint Anselm CollegeJun 24–Jun 251,614 RV4741D+6
University of New HampshireJun 18–Jun 232,232 LV4744D+3
University of New HampshireApr 17–Apr 211,295 LV4942D+7
Emerson CollegeMar 21–Mar 231,000 LV4544D+1
Saint Anselm CollegeMar 16–Mar 181,491 RV4643D+3
yes. every kid.Jan 28–Jan 29563 LV4541D+4
University of New HampshireJan 15–Jan 192,053 LV5045D+5
NHJournal/Praecones AnalyticaDec 26–Dec 28603 RV4236D+6
Guidant Polling and Strategy for One Nation, a group aligned with the Senate Leadership FundR-sponsoredDec 9–Dec 11600 LV4744D+3
Saint Anselm CollegeNov 18–Nov 192,212 RV4441D+3
co/efficientR-sponsoredOct 9–Oct 131,034 LV4542D+3
University of New HampshireSep 17–Sep 231,235 LV4943D+6
co/efficientR-sponsoredSep 10–Sep 12904 LV4643D+3
1892 Polling for One Nation, a group aligned with the Senate Leadership FundR-sponsoredSep 2–Sep 4500 LV4543D+2

Adjusted: after correcting for the pollster's house effect, registered vs. likely voters, and movement in the national environment since the poll; shown for the polls carrying the most weight in today's average. Larger dots in the chart carry the most weight. Last poll: Oct 5, 2026.

The state

Lean D+4: how much more Democratic or Republican than the nation it votes for president.

Presidential vote

← RepublicanDemocratic →2016 presidentD+0.4R+1.8 vs. nation2020 presidentD+7.5D+3.0 vs. nation2024 presidentD+2.8D+4.3 vs. nation

Who lives here

Population
1,394,868
Adults with a B.A.+
41%
White, no degree
53%of adults
  • White 87%
  • Hispanic 5%
  • Black 1%
  • Asian 3%
  • Other / multiracial 5%

American Community Survey 2020–2024, aggregated from census tracts.

Past results

2024 President Vote in this state

814,011 two-party votes · D+2.8 · D+4.3 vs. the nation
✓ Kamala Harris (D)51.4%
Donald Trump (R)48.6%

2020

795,914 votes · D+16.0
✓ Jeanne Shaheen (D)56.6%
Corky Messner (R)41.0%
Justin O'Donnell (L)2.3%

2020 President Vote in this state

790,575 two-party votes · D+7.5 · D+3.0 vs. the nation
✓ Joe Biden (D)53.7%
Donald Trump (R)46.3%

2016 President Vote in this state

694,316 two-party votes · D+0.4 · R+1.8 vs. the nation
✓ Hillary Clinton (D)50.2%
Donald Trump (R)49.8%

2014

486,531 votes · D+3.3
✓ Jeanne Shaheen (D)51.6%
Scott P. Brown (R)48.4%

2008

694,357 votes · D+6.5
✓ Jeanne Shaheen (D)51.6%
John E. Sununu (R)45.3%
"ken" Blevens (L)3.1%

2002

444,542 votes · R+4.5
✓ John E. Sununu (R)51.1%
Jeanne Shaheen (D)46.7%
Ken Blevens (L)2.2%

Also on the ballot in New Hampshire

GovernorCinde WarmingtonKelly Ayotte94%Rep.74%Rep.