Mason County, Illinois: Heartland Swing county. In 2024, voted R+42%. Republican peak: R+42 in 2024.
Key facts
- 2024 presidential margin
- R+42MIT Election Lab
- Political typology
- Heartland SwingAkashic typology
- Population
- 12,7452024 5-year
- Median household income
- $62,8452024 5-year
- White (non-Hispanic)
- 94.6%2024 5-year
- Black
- 0.8%2024 5-year
- Hispanic / Latino
- 1.6%2024 5-year
- Peak Democratic margin
- D+38 in 1932MIT Election Lab
- Peak Republican margin
- R+42 in 2024MIT Election Lab
- Most similar
- Scott County, IN · similarity 0.99
2024 results by precinct
2024 precinct map of Mason CountyPrecinct-level 2024 presidential results for Mason County, with each precinct boundary colored by Democratic-vs-Republican margin.
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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 | +14.8% |
| 1896 | +6.7% |
| 1900 | +10.4% |
| 1904 | +0.2% |
| 1908 | +7.7% |
| 1912 | +29.7% |
| 1916 | +12.0% |
| 1920 | −19.0% |
| 1924 | −14.8% |
| 1928 | −9.8% |
| 1932 | +37.7% |
| 1936 | +21.6% |
| 1940 | −1.4% |
| 1944 | −9.3% |
| 1948 | −0.3% |
| 1952 | −23.9% |
| 1956 | −18.7% |
| 1960 | −6.3% |
| 1964 | +26.3% |
| 1968 | −6.8% |
| 1972 | −25.6% |
| 1976 | +1.3% |
| 1980 | −25.5% |
| 1984 | −10.1% |
| 1988 | −0.3% |
| 1992 | +19.4% |
| 1996 | +14.8% |
| 2000 | −3.2% |
| 2004 | −9.6% |
| 2008 | +5.9% |
| 2012 | −6.3% |
| 2016 | −31.5% |
| 2020 | −39.3% |
| 2024 | −42.2% |
DemocraticRepublican
38 presidential elections
| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| R | 1,773 | 4,464 | 6,374 | ||
| R | 1,985 | 4,654 | 6,785 | ||
| R | 2,014 | 4,058 | 6,493 | ||
| R | 2,867 | 3,265 | 6,296 | ||
| D | 3,542 | 3,141 | 6,808 | ||
| R | 3,215 | 3,907 | 7,183 | ||
| R | 3,192 | 3,411 | 6,772 | ||
| D | 3,385 | 2,430 | 6,444 | ||
| D | 3,969 | 2,473 | 7,702 | ||
| R | 3,406 | 3,424 | 6,855 | ||
| R | 3,354 | 4,109 | 7,486 | ||
| R | 2,680 | 4,644 | 7,693 | ||
| D | 3,947 | 3,847 | 7,849 | ||
| R | 2,901 | 4,897 | 7,810 | ||
| R | 3,365 | 3,899 | 7,853 | ||
| D | 4,857 | 2,833 | 7,690 | ||
| R | 3,824 | 4,337 | 8,180 | ||
| R | 3,199 | 4,677 | 7,889 | ||
| R | 3,061 | 4,982 | 8,047 | ||
| R | 3,503 | 3,525 | 7,074 | ||
| R | 3,282 | 3,959 | 7,262 | ||
| R | 4,416 | 4,541 | 8,998 | ||
| D | 5,278 | 3,395 | 8,731 | ||
| D | 5,681 | 2,551 | 8,300 | ||
| R | 3,246 | 3,956 | 7,221 | ||
| R | 2,536 | 3,522 | 6,680 | ||
| R | 2,595 | 3,842 | 6,579 | ||
| D | 3,886 | 3,029 | 7,136 | ||
| D | 2,173 | 948 | 4,121 | ||
| D | 2,264 | 1,924 | 4,424 | ||
| D | 1,806 | 1,798 | 3,992 | ||
| D | 2,508 | 2,027 | 4,636 | ||
| D | 2,407 | 2,100 | 4,582 | ||
| D | 2,211 | 1,614 | 4,034 | ||
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Demographics
2024 ACS
Race, ethnicity, and ancestry
Click any group to see the ancestries typically reported within it.
German
27.8%
English
15.3%
Irish
12.2%
American
6.3%
Polish
2.6%
Italian
1.6%
Scottish
1.5%
Sample size too small to break out by ancestry reliably.
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: 45.4 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
$62,845
Mason County ranks near the middle of US counties.
Mason County$62,845
Illinois$83,390
United States$80,734
Mason 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
14.8%
Children face moderate poverty.
Children under 1819.6%
Working age (18–64)14.0%
Seniors (65+)10.1%
Source · American Community Survey 5-year estimates, 2024 release.
2024 ACS
Language at home
Population aged 5 and older
97.8%
speak English only
Spanish0.9%
Other Indo-European0.8%
Asian & Pacific Islander0.5%
Source · ACS 5-year estimates, 2024.
2020 religion census
Religious adherents
Adherents per capita by tradition
Source · 2020 US Religion Census. Remaining 68.5% of residents not counted as adherents by any reporting body.
Mason County's population of roughly 16,000 sits along the Illinois River bottomlands, and its electorate has shifted decisively rightward over successive presidential cycles, posting a 42-point Republican margin in 2024.
The Democratic margin here peaked at thirty-eight points in 1932. Between 2020 and 2024 the county moved three points toward the Republican candidate; the 2024 margin was forty-two points.
A population of 12,745, a 95% non-Hispanic-white share, and a median household income of $62,845 describe the county. The county's voting pattern over the last decade is most similar to that of Scott County and Iron 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.
Mason County, Illinois. Akashic. https://akashic.app/county/17125/. Accessed May 20, 2026. License: CC BY 4.0.
License: CC BY 4.0
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Frequently asked questions
How did Mason County, Illinois vote in 2024?
In 2024, Mason County, Illinois voted Republican by 42.2 points (R+42), carried by the Republican candidate. Out of 6,374 votes cast, 1,773 went Democratic and 4,464 went Republican.
What is Mason County, Illinois's political typology?
Akashic places Mason County, Illinois 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 14 times, Republican 20 times, and other 0 times.
When did Mason County, Illinois last vote Democratic?
The most recent presidential election in which Mason County, Illinois voted Democratic was 2008.
How many people live in Mason County, Illinois?
Mason County, Illinois has a population of 12,745 according to the 2024 American Community Survey 5-year estimates from the US Census Bureau.
What is the median household income in Mason County, Illinois?
Median household income in Mason County, Illinois is $62,845 — below the national median of $80,734. The Illinois state median is $83,390.
What is the political history of Mason County, Illinois?
Akashic tracks 38 presidential elections in Mason County, Illinois from 1876 to 2024. Of those, 14 went Democratic and 20 went Republican. The county's typology — "Heartland Swing" — captures where that record, its demographics, and its recent swing place it among American communities.