U.S. House seat · lines in effect since 2022
Iowa's 3rd District
A district of about 816,000 people, 37% of adults with a bachelor's degree. It votes R+3.5 relative to the nation for president.
Source: 2026 results: Iowa Secretary of State; boundaries: Census Bureau TIGER/LineUpdated Nov 7, 2026, 3:01 PM ET
Where it sits among all 435 seats
Every U.S. House seat by partisan lean, from most Democratic to most Republican. Lean is the seat's presidential vote on current lines, relative to the nation.
Democratic
Labels below the bar mark 3 other seats in Iowa.
Source: 99chambers: 2024 and 2020 presidential results on current lines, relative to the nation (2024 weighted 3:1)Updated Oct 16, 2026, 5:19 AM ET
Every race on these lines
Results recomputed from precinct returns as if today's boundaries had always existed, so years compare like for like.
| 2022 | 2024 | 2026 | |
|---|---|---|---|
| U.S. House | R+0.7 | R+3.8 | D+7.3 |
Outlined: the race for this seat itselfBlank: no race that year
Source: 99chambers results archive: precinct results allocated to current lines; 2026: Iowa Secretary of StateUpdated Nov 7, 2026, 3:01 PM ET
Who lives here, compared
Grey bars show the spread of all 435 seats. Small marks are other seats in Iowa. The black marker is IA-3.
Higher than 63% of seats.
Higher than 77% of seats.
Lower than 66% of seats.
Lower than 61% of seats.
Higher than 55% of seats.
Less dense than 82% of seats.
Source: Census Bureau, American Community Survey 2020–2024 5-year estimates, allocated to current linesUpdated Oct 13, 2026, 5:06 AM ET
Seats most like this one
Nearest seats on demographics, density and lean. 2 of the 4 flipped this year.
NY-1935% college gradsD+2.4Held DIA-1
33% college gradsR+7.3Flipped DMI-4
33% college gradsR+5.2Flipped DNE-1
37% college gradsR+12.7Held R
Source: Census Bureau, American Community Survey 2020–2024 5-year estimates, allocated to current lines; 99chambers: 2024 and 2020 presidential results on current lines, relative to the nation (2024 weighted 3:1)Updated Oct 16, 2026, 5:19 AM ET
Who has held it
These lines took effect in 2022.
- Sarah Trone Garriott (D)
2027– · Won 2026 by 7.3 - Zach Nunn (R)
2023–2027 · Won 2022 by 0.7, 2024 by 3.8
Source: Past results: 99chambers results archive (MEDSL, Klarner, state election offices)