2024 results by precinct
—
Margin—
Turnout—
Harris +50Trump +50
Real precinct boundaries. Hover for vote totals.
38 presidential elections
| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | D | 34,126 | 28,061 | 63,458 | |
| 2020 | D | 36,691 | 28,603 | 66,947 | |
| 2016 | D | 32,298 | 26,998 | 63,994 | |
| 2012 | D | 39,157 | 24,934 | 65,217 | |
| 2008 | D | 42,210 | 25,364 | 68,401 | |
| 2004 | D | 39,880 | 29,663 | 69,972 | |
| 2000 | D | 37,957 | 25,194 | 65,095 | |
| 1996 | D | 34,822 | 20,626 | 60,955 | |
| 1992 | D | 37,412 | 23,212 | 72,039 | |
| 1988 | D | 40,174 | 27,412 | 67,901 | |
| 1984 | D | 40,208 | 35,121 | 75,672 | |
| 1980 | R | 30,045 | 34,788 | 71,775 | |
| 1976 | D | 35,994 | 34,007 | 71,261 | |
| 1972 | R | 32,529 | 37,548 | 70,330 | |
| 1968 | D | 34,506 | 30,404 | 70,140 | |
| 1964 | D | 41,759 | 23,714 | 65,473 | |
| 1960 | D | 33,812 | 32,534 | 66,454 | |
| 1956 | R | 29,145 | 31,342 | 60,605 | |
| 1952 | R | 27,879 | 32,933 | 60,912 | |
| 1948 | D | 24,542 | 22,192 | 47,211 | |
| 1944 | D | 30,102 | 23,980 | 54,262 | |
| 1940 | D | 35,240 | 25,629 | 61,101 | |
| 1936 | D | 32,741 | 19,487 | 53,027 | |
| 1932 | D | 24,676 | 21,205 | 46,549 | |
| 1928 | R | 14,334 | 27,246 | 41,776 | |
| 1924 | R | 3,631 | 20,563 | 35,647 | |
| 1920 | R | 5,208 | 21,908 | 30,719 | |
| 1916 | R | 10,914 | 16,169 | 30,322 | |
| 1912 | D | 3,997 | 2,394 | 15,289 | |
| 1908 | R | 4,739 | 8,196 | 14,781 | |
| 1904 | R | 2,156 | 8,152 | 13,203 | |
| 1900 | R | 4,786 | 8,299 | 13,556 | |
| 1896 | R | 4,692 | 7,323 | 12,191 | |
| 1892 | R | 4,034 | 5,052 | 9,645 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Demographics
Race, ethnicity, and ancestry
Click any group to see the ancestries typically reported within it.
American
100.0%
Polish
1.1%
African American
9.1%
Multiple ancestry combinations reported; no single grouping above 1%.
American Indian, Alaska Native, Native Hawaiian, and Pacific Islander combined.
Source · American Community Survey 5-year estimates, 2024 release. Ancestry is a self-reported, multiple-response item; ancestry percentages do not sum to the parent race percentage.
Age distribution by sex
Median age: 40.3 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.
Median household income
2024 inflation-adjusted dollars
$67,159
Rock Island County ranks near the middle of US counties.
Rock Island County$67,159
Illinois$83,390
United States$80,734
Source · American Community Survey 5-year estimates, 2024 release.
Poverty rate
All persons below federal poverty line
15.5%
Children face moderate poverty.
Children under 1818.0%
Working age (18–64)100.0%
Seniors (65+)18.0%
Source · American Community Survey 5-year estimates, 2024 release.
Language at home
Population aged 5 and older
0.0%
speak English only
Source · ACS 5-year estimates, 2024.
Religious adherents
Adherents per capita by tradition
Source · 2020 US Religion Census. Remaining 68.4% of residents not counted as adherents by any reporting body.
Rock Island anchors Illinois's Quad Cities metro along the Iowa border, where a unionized manufacturing heritage and a diverse urban core in Rock Island and Moline have kept the county reliably left of center in statewide contests.
The Democratic margin in Rock Island County reached its widest at twenty-eight points in 1964. The margin in 2024 was ten points — still decisive.
Rock Island County's loyalty is rooted in its place. Median household income of $67,159, a 72% non-Hispanic-white share, and a population of 142,757 together describe a community whose political habits are deeply settled. The county's voting pattern over the last decade is most similar to that of Costilla County and Genesee County.
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