NH-1 · House

The district, in brief

New Hampshire's 1st is described in the text as taking in Manchester, the Seacoast and the Lakes Region. The lines are the map first used in 2022 and are not redrawn for this cycle. The facts record a 2024 presidential two-party margin of 2.0 for the Democrat on these lines, and a 2024 House two-party margin of 8.07 for the Democrat.

The seat is open: the incumbent, Democrat Chris Pappas, re-elected with 54.0% in 2024, is retiring to run for Senate. The Democratic nominee is Stefany Shaheen, a former Portsmouth city councilor and daughter of U.S. Senator Jeanne Shaheen, who won a crowded primary with 36.9% over Maura Sullivan (34.7%) and Carleigh Beriont (22.5%). The Republican nominee is Anthony DiLorenzo, who took 51.5% in his primary against Hollie Noveletsky (26.2%); the text gives no background for him. As of March 31, 2026 Shaheen had raised $1,800,994 with $1,113,137 on hand and DiLorenzo $1,290,475 with $827,267 on hand.

Every rater listed calls the seat D: Decision Desk HQ (July 14, 2026), the Cook Political Report (February 6, 2025), Inside Elections (March 7, 2025) and Sabato's Crystal Ball (July 15, 2025). One general-election poll is recorded, from the University of New Hampshire (September 17–21, 2026): Shaheen 46%, DiLorenzo 42%, 11% undecided.

A paragraph quoting a model forecast from the day this brief was written is omitted; the current forecast is at the top of this page.

The facts, each beside its sentence

Not in the source: The text gives no background or prior office for the Republican nominee Anthony DiLorenzo; his nominee line is missing from the archived text.; The district description is truncated in the text; only 'Manchester, the Seacoast and the Lakes Region' survives.; No Silver Bulletin rating is listed, and no rating finer than 'D' is given.; No general-election fundraising table (post-primary) is given; figures are as of March 31, 2026.; The model's basis says no district polls, but the text records one general-election poll (University of New Hampshire, September 17–21, 2026).

Read from the district's section of Wikipedia's state page (CC BY-SA), archived as 1d36a9ee2f88; written by claude-fable-5-1 (batch reader) on 2026-09-30 and checked mechanically: every quote occurs verbatim in the archived text, every number in the brief occurs in the inputs. No probability here is the reader's.

Who holds the seat now

Chris Pappas (Democrat), in this chamber since 2019, 4 terms. Committees: House Committee on Transportation and Infrastructure; House Committee on Veterans' Affairs.

From the congress-legislators dataset (CC0), archived as ae8cb9477c48. For a Senate race this lists both of the state's senators; the one whose term ends in the election year holds the seat on the ballot. For a House district redrawn for 2026 it is the member elected under the old lines with this number, who may be running elsewhere; the dossier above names who is running here.

How it has voted for president

A shift of 3.4 points toward the Democrats from 2016 to 2024. county returns placed on the current lines by 2020 block population; MEDSL county file (2016), an MIT-licensed county file (2020, checked against certified state results) and MEDSL precinct returns (2024). For a district split across counties this is an estimate, and where the state published the exact 2024 figure for these lines, that exact figure is the one the model uses.

Who are the voters?

Of about 495,988 adults 25 and over. In 2020 the district voted 53.0% Democratic (two-party) for president. With the same preferences and a 2022-style midterm turnout, it would vote 54.1% Democratic: the midterm electorate alone moves the margin 2.1 points toward Democrats. Group shares are estimated from how results vary across the state's census tracts (ecological inference, anchored to Pew's 2020 validated-voter figures) and calibrated to this district's actual 2020 vote; turnout is the Census survey's state rate by race and national rate by education, whose state samples carry margins of several points.

Not answered here: how each group will vote in 2026. These are 2020 preferences; this profile is description, not yet an input to the forecast.

The money

FEC bulk candidate summaries through September 30, 2026; $6,528,517 of independent expenditures for or against these candidates this cycle (FEC Schedule E, types 24E and 24A), which is the parties' and outside groups' own revealed view of whether this seat is in play.

The district in numbers

ACS 5-year 2023, the Census Bureau's own tabulation of this district (118th Congress lines). Unemployment is the BLS county series placed on the district by block population, not seasonally adjusted, so changes are same-month comparisons. Income, transfers and jobs are BEA county accounts placed the same way, compared with the average district. Every other figure is a named column of a named table in the Bureau's summary file, archived before it was read. This is what a reader knows about a district before looking at a poll; the model does not yet use it, and whether it should is a registered question.

Who is favoured, and by how much?

The 90% interval runs from -0.9 to +29.1 points, D-R. It is wide because this district has never been polled.

What is this built on?

A model trained on every contested House race 2012-2024 predicts this district's lean from its own record: presidential and House results on the current lines, incumbency, both candidates' prior offices, outside and party money before 1 October, demographics and public-assistance shares from the Census release before the election, local unemployment and income, and religious tradition. The national margin comes from presidential approval, the economy, the midterm penalty and the generic ballot corrected for its measured lean. Draws share national and state errors, so the seat total and this district come from the same simulation.

Not answered here: district polls, which are not yet folded in.

Why does the model say this?

Each figure is how far this district's predicted lean moves when that one feature is set to the typical value across 2026 districts, everything else held: 2024 presidential lean (D+3.5): 5.3 pts toward the Democrat; PAC money balance: 2.4 pts toward the Democrat; experience gap (+1 levels, D minus R): 2.0 pts toward the Democrat; 2024 House lean (D+10.8): 1.2 pts toward the Democrat; hispanic share (4.8%): 1.1 pts toward the Democrat.

How sure is it, and of what?

Total sd 9.12 points, made of the seat's own volatility 91%, correlated polling error 9%. The decomposition is stored with the forecast rather than reconstructed, so a probability whose dominant input is a placeholder is visibly that.

Not answered here: a nowcast. 'If ballots were cast today' needs something that observes today, and for a House district nothing does. Publishing the election-day figure under both labels would make one forecast look like two.

How was this number made?

Run 6f211e6f-2bdc-4dda-8f72-81fc628dab0b, house_district_prior/0.2.0, as of 2026-10-02. Promoted by a pre-registered gate: on 2016-2022 its Brier score was 0.036 against 0.049 for the previous method, and on a single 2024 run 0.023 against 0.032 (experiments/district_gate_result.md, with an independent review).