Jefferson, Iowa — Presidential Election Results
Jefferson, Iowa has voted Republican in 4 of the last 7 presidential elections on record (2000–2024). It most recently flipped to Republican in 2016. In 2024, it was 6.5 pts more Dem. than Iowa overall.
Jump to year: 2000 · 2004 · 2008 · 2012 · 2016 · 2020 · 2024
Full Election History, 2000–2024
| Year | Winner | Party | Votes | Vote Share | Margin | Total Votes Cast | Swing | Vs. Iowa |
|---|---|---|---|---|---|---|---|---|
| 2000 | George W. Bush | Republican | 3,248 | 43.0% | 5.1 pts (385 votes) | 7,548 | — | 6.6 pts more Rep. |
| 2004 | John Kerry | Democratic | 4,490 | 54.2% | 10.2 pts (842 votes) | 8,281 | +16.6 pts | 11.0 pts more Dem. |
| 2008 | Barack Obama | Democratic | 5,070 | 58.7% | 20.2 pts (1,746 votes) | 8,631 | +10.5 pts | 11.1 pts more Dem. |
| 2012 | Barack Obama | Democratic | 4,798 | 56.2% | 16.0 pts (1,362 votes) | 8,530 | -4.3 pts | 10.6 pts more Dem. |
| 2016 | Donald Trump | Republican | 3,748 | 46.0% | 0.5 pts (38 votes) | 8,156 | -17.1 pts | 9.6 pts more Dem. |
| 2020 | Donald J Trump | Republican | 4,476 | 50.0% | 1.8 pts (157 votes) | 8,959 | -1.3 pts | 6.8 pts more Dem. |
| 2024 | Donald J Trump | Republican | 4,353 | 52.2% | 6.8 pts (565 votes) | 8,346 | -5.2 pts | 6.5 pts more Dem. |
Population Context
Total Census Bureau population estimate for the county that year, and recorded votes as a share of that total population. This is a population-based figure, not a turnout rate against eligible or registered voters, which this site does not calculate.
| Year | County Population | Votes Cast (% of Population) |
|---|---|---|
| 2000 | 16,189 | 46.6% of population |
| 2004 | 16,298 | 50.8% of population |
| 2008 | 16,607 | 52.0% of population |
| 2012 | 17,278 | 49.4% of population |
| 2016 | 18,063 | 45.2% of population |
| 2020 | 15,699 | 57.1% of population |
| 2024 | 15,781 | 52.9% of population |
Trend
Between 2000 and 2024, the two-party presidential margin in Jefferson shifted 0.6 points toward the Republican candidate, based on recorded county returns. This reflects the vote totals in this dataset only; no claim is made here about the causes of that shift.
Margin Over Time
Democratic candidate's margin (percentage points, two-party vote share). Positive values favor the Democratic candidate; negative values favor the Republican candidate.
Bellwether Status
Jefferson has matched the national popular winner in 5 of the last 7 presidential elections (71%), and Iowa's own statewide winner in 5 of 7 (71%). Compare every county on the bellwether counties page.
Related Pages
Other Iowa Counties
Frequently Asked Questions
How has Jefferson voted in presidential elections since 2000?
Since 2000, Jefferson has voted Democratic in 3 of 7 recorded presidential elections and Republican in 4 of 7, based on county-level returns through 2024.
What was the closest presidential election in Jefferson?
Jefferson's closest recorded margin was in 2016, when Donald Trump (Republican) won by 0.5 points (38 votes) out of 8,156 total votes cast.
Has Jefferson ever flipped between parties?
Yes. Jefferson changed which party won the county in: 2004, 2016, based on the 2000-2024 record on this page.
What is the largest presidential election margin recorded in Jefferson?
The widest margin on record for Jefferson was in 2008, when Barack Obama (Democratic) won by 20.8 points.
How many votes were cast in Jefferson relative to its population?
In 2024, 8,346 votes were recorded in Jefferson against a total population of 15,781 (52.9% of the total population). This is a population-based figure, not a turnout rate against eligible or registered voters, which this site does not calculate.
Is Jefferson a presidential bellwether county?
Jefferson has matched the national popular winner in 5 of the last 7 presidential elections (71%), and Iowa's own statewide winner in 5 of 7 (71%).