O'Brien, Iowa — Presidential Election Results
O'Brien, Iowa has voted Republican in 7 of the last 7 presidential elections on record (2000–2024). In 2024, it was 48.1 pts more Rep. 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 | 4,674 | 66.4% | 35.5 pts (2,504 votes) | 7,044 | — | 36.9 pts more Rep. |
| 2004 | George W. Bush | Republican | 5,328 | 68.9% | 38.8 pts (2,998 votes) | 7,731 | -2.6 pts | 38.5 pts more Rep. |
| 2008 | John McCain | Republican | 4,894 | 66.7% | 34.9 pts (2,556 votes) | 7,333 | +3.8 pts | 45.0 pts more Rep. |
| 2012 | Mitt Romney | Republican | 5,266 | 71.7% | 44.9 pts (3,297 votes) | 7,341 | -10.2 pts | 51.5 pts more Rep. |
| 2016 | Donald Trump | Republican | 5,752 | 77.7% | 59.9 pts (4,437 votes) | 7,406 | -17.2 pts | 52.7 pts more Rep. |
| 2020 | Donald J Trump | Republican | 5,871 | 77.8% | 57.0 pts (4,302 votes) | 7,551 | +5.0 pts | 49.2 pts more Rep. |
| 2024 | Donald J Trump | Republican | 5,998 | 79.7% | 60.7 pts (4,570 votes) | 7,525 | -3.7 pts | 48.1 pts more Rep. |
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 | 15,067 | 46.8% of population |
| 2004 | 14,564 | 53.1% of population |
| 2008 | 14,332 | 51.2% of population |
| 2012 | 14,156 | 51.9% of population |
| 2016 | 13,926 | 53.2% of population |
| 2020 | 14,149 | 53.4% of population |
| 2024 | 14,260 | 52.8% of population |
Trend
Between 2000 and 2024, the two-party presidential margin in O'Brien shifted 25.0 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
O'Brien has matched the national popular winner in 4 of the last 7 presidential elections (57%), and Iowa's own statewide winner in 4 of 7 (57%). Compare every county on the bellwether counties page.
Related Pages
Other Iowa Counties
Frequently Asked Questions
How has O'Brien voted in presidential elections since 2000?
Since 2000, O'Brien has voted Democratic in 0 of 7 recorded presidential elections and Republican in 7 of 7, based on county-level returns through 2024.
What was the closest presidential election in O'Brien?
O'Brien's closest recorded margin was in 2008, when John McCain (Republican) won by 35.3 points (2,556 votes) out of 7,333 total votes cast.
Has O'Brien ever flipped between parties?
Not in the 2000-2024 record on this page -- O'Brien has voted for the same party in every recorded presidential election in that span.
What is the largest presidential election margin recorded in O'Brien?
The widest margin on record for O'Brien was in 2016, when Donald Trump (Republican) won by 62.8 points.
How many votes were cast in O'Brien relative to its population?
In 2024, 7,525 votes were recorded in O'Brien against a total population of 14,260 (52.8% 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 O'Brien a presidential bellwether county?
O'Brien has matched the national popular winner in 4 of the last 7 presidential elections (57%), and Iowa's own statewide winner in 4 of 7 (57%).