Decatur County, Iowa: Heartland Swing county. In 2024, voted R+47%. Republican peak: R+47 in 2024.
Key facts
- 2024 presidential margin
- R+47MIT Election Lab
- Political typology
- Heartland SwingAkashic typology
- Population
- 7,7592024 5-year
- Median household income
- $59,0442024 5-year
- White (non-Hispanic)
- 91.8%2024 5-year
- Black
- 1.3%2024 5-year
- Hispanic / Latino
- 3.5%2024 5-year
- Peak Democratic margin
- D+37 in 1964MIT Election Lab
- Peak Republican margin
- R+47 in 2024MIT Election Lab
- Most similar
- Monroe County, IA · similarity 0.99
2024 results by precinct
2024 precinct map of Decatur CountyPrecinct-level 2024 presidential results for Decatur County, with each precinct boundary colored by Democratic-vs-Republican margin.
—
Margin—
Turnout—
Harris +50Trump +50
Real precinct boundaries. Hover for vote totals.
presidential history
Presidential margin, 1876–2024
Democratic minus Republican, by election
| Year | Margin (D minus R) |
|---|---|
| 1876 | No data |
| 1880 | No data |
| 1884 | No data |
| 1888 | No data |
| 1892 | −9.8% |
| 1896 | +2.0% |
| 1900 | −7.9% |
| 1904 | −21.2% |
| 1908 | −8.3% |
| 1912 | +7.8% |
| 1916 | +3.6% |
| 1920 | −23.3% |
| 1924 | −22.4% |
| 1928 | −19.0% |
| 1932 | +24.8% |
| 1936 | +10.7% |
| 1940 | +6.0% |
| 1944 | +6.1% |
| 1948 | +10.8% |
| 1952 | −17.8% |
| 1956 | −1.9% |
| 1960 | −11.5% |
| 1964 | +36.6% |
| 1968 | −4.4% |
| 1972 | −16.5% |
| 1976 | +16.3% |
| 1980 | −3.5% |
| 1984 | −0.1% |
| 1988 | +21.7% |
| 1992 | +13.8% |
| 1996 | +15.4% |
| 2000 | −6.2% |
| 2004 | −5.7% |
| 2008 | −0.8% |
| 2012 | −4.1% |
| 2016 | −28.9% |
| 2020 | −39.3% |
| 2024 | −46.9% |
DemocraticRepublican
38 presidential elections
| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| R | 957 | 2,711 | 3,739 | ||
| R | 1,120 | 2,615 | 3,804 | ||
| R | 1,201 | 2,296 | 3,784 | ||
| R | 1,791 | 1,947 | 3,833 | ||
| R | 1,986 | 2,020 | 4,102 | ||
| R | 1,859 | 2,088 | 4,011 | ||
| R | 1,674 | 1,903 | 3,709 | ||
| D | 1,846 | 1,287 | 3,623 | ||
| D | 1,866 | 1,316 | 3,986 | ||
| D | 2,192 | 1,406 | 3,627 | ||
| R | 2,098 | 2,104 | 4,242 | ||
| R | 2,048 | 2,212 | 4,640 | ||
| D | 2,698 | 1,932 | 4,707 | ||
| R | 1,880 | 2,638 | 4,593 | ||
| R | 2,057 | 2,261 | 4,588 | ||
| D | 3,331 | 1,542 | 4,885 | ||
| R | 2,411 | 3,039 | 5,457 | ||
| R | 2,806 | 2,912 | 5,725 | ||
| R | 2,521 | 3,621 | 6,168 | ||
| D | 3,172 | 2,547 | 5,803 | ||
| D | 3,316 | 2,934 | 6,268 | ||
| D | 3,938 | 3,494 | 7,448 | ||
| D | 4,131 | 3,327 | 7,494 | ||
| D | 3,591 | 2,148 | 5,830 | ||
| R | 2,675 | 3,942 | 6,675 | ||
| R | 1,693 | 3,221 | 6,835 | ||
| R | 2,592 | 4,187 | 6,845 | ||
| D | 2,111 | 1,962 | 4,135 | ||
| D | 1,659 | 1,351 | 3,928 | ||
| R | 1,809 | 2,149 | 4,091 | ||
| R | 1,548 | 2,430 | 4,158 | ||
| R | 2,058 | 2,415 | 4,539 | ||
| D | 2,362 | 2,268 | 4,680 | ||
| R | 1,486 | 1,856 | 3,780 | ||
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Demographics
2024 ACS
Race, ethnicity, and ancestry
Click any group to see the ancestries typically reported within it.
German
19.6%
English
14.0%
Irish
10.2%
American
4.7%
Scottish
2.6%
French
1.5%
Polish
1.4%
African American
1.0%
Multiple ancestry combinations reported; no single grouping above 1%.
Sample size too small to break out by ancestry reliably.
American Indian, Alaska Native, Native Hawaiian, and Pacific Islander combined.
Source · American Community Survey 5-year estimates, 2024 release. Hispanic/Latino is an ethnicity that overlaps the race categories, so these shares can total more than 100%. Ancestry is a self-reported, multiple-response item; ancestry percentages do not sum to the parent race percentage.
2024 ACS
Age distribution by sex
Median age: 36.1 in this county, 39.1 nationally
Male
Age
Female
85+
75–84
65–74
55–64
45–54
35–44
25–34
18–24
5–17
<5
Source · American Community Survey 5-year estimates, 2024 release.
2024 ACS
Median household income
Inflation-adjusted dollars
$59,044
Decatur County ranks near the middle of US counties.
Decatur County$59,044
Iowa$75,059
United States$80,734
Decatur County ranks near the middle of US counties by median household income.
Source · American Community Survey 5-year estimates, 2024 release.
2024 ACS
Poverty rate
All persons below federal poverty line
14.6%
Children face moderate poverty.
Children under 1820.1%
Working age (18–64)12.8%
Seniors (65+)13.8%
Source · American Community Survey 5-year estimates, 2024 release.
2024 ACS
Language at home
Population aged 5 and older
94.8%
speak English only
Other Indo-European3.3%
Spanish0.8%
Asian & Pacific Islander0.7%
Other languages0.5%
Source · ACS 5-year estimates, 2024.
2020 religion census
Religious adherents
Adherents per capita by tradition
Source · 2020 US Religion Census. Remaining 69.1% of residents not counted as adherents by any reporting body.
Decatur County's small population and agricultural economy mirror the broader rural Iowa shift toward wide Republican margins — the 2024 gap of nearly 47 points reflects a voting pattern that has grown steadily since 2000.
The Democratic margin here peaked at thirty-seven points in 1964. Between 2020 and 2024 the county moved eight points toward the Republican candidate; the 2024 margin was forty-seven points.
A population of 7,759, a 92% non-Hispanic-white share, and a median household income of $59,044 describe the county. The county's voting pattern over the last decade is most similar to that of Monroe County and Greene County.
Most similar counties
Compare two places, side by side
Twelve curated comparisons line up election history, demographics, and the divergence story for two places at a glance. Browse all comparisons →
Cite this page
All citations released under CC BY 4.0. Attribution: Akashic Intelligence.
Decatur County, Iowa. Akashic. https://akashic.app/county/19053/. Accessed May 20, 2026. License: CC BY 4.0.
License: CC BY 4.0
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Frequently asked questions
How did Decatur County, Iowa vote in 2024?
In 2024, Decatur County, Iowa voted Republican by 46.9 points (R+47), carried by the Republican candidate. Out of 3,739 votes cast, 957 went Democratic and 2,711 went Republican.
What is Decatur County, Iowa's political typology?
Akashic places Decatur County, Iowa in the "Heartland Swing" typology — Industrial Midwest swing counties drifting steadily toward the Republican Party. The typology is a data-driven cluster built from vote share, vote swing, race and ethnicity, income, language spoken at home, religion, and ancestry. Across 38 elections in the dataset, the county has voted Democratic 13 times, Republican 21 times, and other 0 times.
When did Decatur County, Iowa last vote Democratic?
The most recent presidential election in which Decatur County, Iowa voted Democratic was 1996.
How many people live in Decatur County, Iowa?
Decatur County, Iowa has a population of 7,759 according to the 2024 American Community Survey 5-year estimates from the US Census Bureau.
What is the median household income in Decatur County, Iowa?
Median household income in Decatur County, Iowa is $59,044 — below the national median of $80,734. The Iowa state median is $75,059.
What is the political history of Decatur County, Iowa?
Akashic tracks 38 presidential elections in Decatur County, Iowa from 1876 to 2024. Of those, 13 went Democratic and 21 went Republican. The county's typology — "Heartland Swing" — captures where that record, its demographics, and its recent swing place it among American communities.