KY-4 · House

The district, in brief

Kentucky's 4th, on the map first used in 2022, is located in the northeastern part of the state along the Ohio River, including the suburbs of Cincinnati and the eastern suburbs of Louisville.

The incumbent, Republican Thomas Massie, re-elected unopposed in 2024, is not on the November ballot: on May 19 Ed Gallrein, a farmer, retired Navy SEAL and 2024 candidate for Kentucky's 7th Senate district, won the Republican nomination 54.9% to 45.1%. The text ties the primary to Massie's clashes with Donald Trump, who had called for a challenger by March 2025. It became the most expensive U.S. House primary in American history, passing $25.6 million in ad spending by May 11 and $32 million by May 17, with pro-Israel groups accounting for over $9 million against Massie. The Democratic nominee is Melissa Strange, a businesswoman, who won her primary 72.4% to 27.6% over Jesse Brewer. Libertarian Jeremy Todd is also on the ballot. As of June 30, 2026 Gallrein had raised $3,567,323 with $179,309 on hand; Strange had raised $94,463 with $11,145 on hand.

Every rater listed calls the seat R: Decision Desk HQ (July 14, 2026), the Cook Political Report (February 6, 2025), Inside Elections (March 7, 2025) and Sabato's Crystal Ball (June 3, 2025). The text's polls are all of the Republican primary; the last, Quantus Insights (R) on May 11–12, 2026, had Gallrein 53%, Massie 45%. There are no general-election polls and no presidential results.

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: No general-election polls; every poll in the text is of the Republican primary, and the model's basis says no district polls.; No presidential results appear in the text; the only presidential figure is the facts' 2024 baseline.; The facts' 2024 result is unopposed, so there is no prior contested margin on these lines later than 2022.; Ratings are given only as R, with no Lean/Likely/Safe gradation, and all predate the primary except Decision Desk HQ. Endorsement sections are empty.; The text does not say whether Massie has endorsed anyone or whether Trump endorsed Gallrein, beyond the pro-Trump group's Hegseth visit.

Read from the district's section of Wikipedia's state page (CC BY-SA), archived as 4c6b2ef6af16; 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

Thomas Massie (Republican), in this chamber since 2012, 8 terms. Committees: House Committee on Transportation and Infrastructure; House Committee on the Judiciary.

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 2.7 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 512,303 adults 25 and over. In 2020 the district voted 33.4% Democratic (two-party) for president. With the same preferences and a 2022-style midterm turnout, it would vote 34.1% Democratic: the midterm electorate alone moves the margin 1.5 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 June 30, 2026; $26,158,478 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 -37.2 to -7.6 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 (R+34.7): 26.2 pts toward the Republican; 2024 House lean: 4.3 pts toward the Republican; total outside/party money: 3.1 pts toward the Democrat; asian share (1.1%): 1.0 pts toward the Republican; hispanic share (4.5%): 0.4 pts toward the Democrat.

How sure is it, and of what?

Total sd 9.05 points, made of the seat's own volatility 90%, correlated polling error 10%. 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 00a09d4b-7980-4ec5-ada0-077968a87242, 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).