Presidential elections · 2000–2024
O'Brien County, IA — Presidential Election Results (2000–2024)
In 2024, O'Brien County, Iowa voted for Donald J. Trump (Republican) by R+60.7 — 1,428 Democratic to 5,998 Republican of 7,525 votes cast. From 2020 to 2024 it shifted 3.7 points toward Republicans. That makes it 47.5 points more Republican than Iowa overall (R+13.2).
Data: MIT Election Data & Science Lab, Harvard Dataverse.
Margin by election, 2000–2024
Democratic minus Republican, in points of all votes cast — blue bars Democratic, red Republican.
Every election in O'Brien County
| Year | Democratic | Republican | Other | Dem share | Rep share | Margin |
|---|---|---|---|---|---|---|
| 2024 | 1,428 | 5,998 | 99 | 19.0% | 79.7% | R+60.7 |
| 2020 | 1,569 | 5,871 | 111 | 20.8% | 77.8% | R+57.0 |
| 2016 | 1,315 | 5,752 | 339 | 17.8% | 77.7% | R+59.9 |
| 2012 | 1,969 | 5,266 | 106 | 26.8% | 71.7% | R+44.9 |
| 2008 | 2,338 | 4,894 | 101 | 31.9% | 66.7% | R+34.9 |
| 2004 | 2,330 | 5,328 | 73 | 30.1% | 68.9% | R+38.8 |
| 2000 | 2,170 | 4,674 | 200 | 30.8% | 66.4% | R+35.5 |
O'Brien County presidential elections — FAQ
Who carried O'Brien County in the 2024 presidential election?+
Donald J. Trump (Republican) carried O'Brien County, Iowa in 2024 by R+60.7, with 7,525 votes cast. Data: MIT Election Data & Science Lab.
How did O'Brien County shift between 2020 and 2024?+
O'Brien County shifted 3.7 points toward Republicans between 2020 (R+57.0) and 2024 (R+60.7).
Is O'Brien County more Democratic or Republican than Iowa overall?+
In 2024, O'Brien County went R+60.7 while Iowa overall went R+13.2 — 47.5 points more Republican than the state.
Where does this election data come from?+
County-level presidential returns (2000–2024) come from the MIT Election Data and Science Lab (MEDSL), published on the Harvard Dataverse. pumsdata is an independent product that makes the data easy to map and compare, and is not affiliated with MEDSL or Harvard.