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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.

What's the difference?

Iowa › Statewide offices · November 3, 2026 · Updated Oct 16, 2026

Iowa Auditor

Projected flip: Democratic-held seat, Republicans favored (69%).

Cournoyer is favored to win: Cournoyer wins in about 2 of every 3 simulations.

Wettach (D)
31%
chance of winning
Cournoyer (R)
69%
Average margin
R+3.2
80% of outcomes
R+12 to D+6
Partisan lean
R+12
Polls
No pollsmodel only

Flip risk: Democratic-held seat, a toss-up (52% chance it changes parties).

A toss-up: each side wins about half the simulations.

Wettach (D)
48%
chance of winning
Cournoyer (R)
52%
Average margin
R+0.4
80% of outcomes
R+14 to D+13
Partisan lean
R+12
Polls
No pollsmodel only

Range of outcomes

R+3.2R+20R+10EvenD+10D+20
R+0.4R+30R+20R+10EvenD+10D+20D+30

How the odds have moved

Chance of winning by forecast date.

0%25%50%75%100%AugSepOctNovNov 3Wettach 31%Cournoyer 69%

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

0%25%50%75%100%AugSepOctNovNov 3Wettach 48%Cournoyer 52%

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

The candidates

What goes into the forecast

Every ingredient's estimate of the final margin.

National environment
D+9.5Election Day forecast
Iowa state offices
+1.4Polls for governor, statewide and legislative races · details
Environment here
D+10.9Used by the fundamentals
← RepublicanDemocratic →Lean + environmentUsual vote, shifted by the national and state moodR+1.7Fundamentals modelAdds incumbency, past results, money andexperienceR+3.9Polls in similar placesPolling of similar races in Iowa and look-alikeplacesR+2.1Polling averageNo polls of this racenot availableHorizon forecastPolls + fundamentals, projected to Election DayR+3.2Pulse forecastPolls (and polling of similar places) only, todayR+0.4

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)0
Elected-experience edge-1
First-term incumbent0
Seat's last result vs. expectation0
Incumbent's last result vs. expectation0

Polls

No public polls of this race. The forecast relies on fundamentals and on polling of similar places in the state.

The state

Lean R+12: how much more Democratic or Republican than the nation it votes for president.

Presidential vote

← RepublicanDemocratic →2016 presidentR+10.1R+12.4 vs. nation2020 presidentR+8.4R+12.9 vs. nation2024 presidentR+13.4R+11.9 vs. nation

Who lives here

Population
3,210,507
Adults with a B.A.+
31%
White, no degree
58%of adults
  • White 82%
  • Hispanic 7%
  • Black 4%
  • Asian 3%
  • Other / multiracial 4%

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

Past results

2024 President Vote in this state

1,634,297 two-party votes · R+13.4 · R+11.9 vs. the nation
✓ Donald Trump (R)56.7%
Kamala Harris (D)43.3%

2020 President Vote in this state

1,656,733 two-party votes · R+8.4 · R+12.9 vs. the nation
✓ Donald Trump (R)54.2%
Joe Biden (D)45.8%

2016 President Vote in this state

1,454,652 two-party votes · R+10.1 · R+12.4 vs. the nation
✓ Donald Trump (R)55.1%
Hillary Clinton (D)44.9%

Also on the ballot in Iowa

U.S. SenateJosh TurekAshley HinsonFlip riskFlip risk53%Rep.50%Rep. GovernorRob SandZach LahnD flipD flip83%Dem.79%Dem.