Presidential elections · 2000–2024
Jefferson County, IA — Presidential Election Results (2000–2024)
In 2024, Jefferson County, Iowa voted for Donald J. Trump (Republican) by R+6.8 — 3,788 Democratic to 4,353 Republican of 8,346 votes cast. From 2020 to 2024 it shifted 5.0 points toward Republicans. That makes it 6.4 points more Democratic 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 Jefferson County
| Year | Democratic | Republican | Other | Dem share | Rep share | Margin |
|---|---|---|---|---|---|---|
| 2024 | 3,788 | 4,353 | 205 | 45.4% | 52.2% | R+6.8 |
| 2020 | 4,319 | 4,476 | 164 | 48.2% | 50.0% | R+1.8 |
| 2016 | 3,710 | 3,748 | 698 | 45.5% | 46.0% | R+0.5 |
| 2012 | 4,798 | 3,436 | 296 | 56.2% | 40.3% | D+16.0 |
| 2008 | 5,070 | 3,324 | 237 | 58.7% | 38.5% | D+20.2 |
| 2004 | 4,490 | 3,648 | 143 | 54.2% | 44.1% | D+10.2 |
| 2000 | 2,863 | 3,248 | 1,437 | 37.9% | 43.0% | R+5.1 |
Jefferson County presidential elections — FAQ
Who carried Jefferson County in the 2024 presidential election?+
Donald J. Trump (Republican) carried Jefferson County, Iowa in 2024 by R+6.8, with 8,346 votes cast. Data: MIT Election Data & Science Lab.
How did Jefferson County shift between 2020 and 2024?+
Jefferson County shifted 5.0 points toward Republicans between 2020 (R+1.8) and 2024 (R+6.8).
Is Jefferson County more Democratic or Republican than Iowa overall?+
In 2024, Jefferson County went R+6.8 while Iowa overall went R+13.2 — 6.4 points more Democratic 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.