| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 3,153 | 7,814 | 11,140 | |
| 2020 | R | 3,454 | 7,737 | 11,335 | |
| 2016 | R | 3,309 | 6,638 | 10,682 | |
| 2012 | R | 4,947 | 5,601 | 10,674 | |
| 2008 | D | 5,302 | 4,922 | 10,387 | |
| 2004 | R | 4,689 | 5,762 | 10,524 | |
| 2000 | R | 4,463 | 4,879 | 9,568 | |
| 1996 | D | 4,333 | 3,392 | 8,790 | |
| 1992 | D | 3,800 | 3,439 | 9,475 | |
| 1988 | D | 5,437 | 3,701 | 9,273 | |
| 1984 | R | 4,960 | 5,021 | 10,077 | |
| 1980 | R | 3,885 | 5,017 | 9,737 | |
| 1976 | D | 5,333 | 4,094 | 9,608 | |
| 1972 | D | 4,608 | 4,415 | 9,285 | |
| 1968 | D | 4,809 | 3,927 | 9,202 | |
| 1964 | D | 7,807 | 2,387 | 10,207 | |
| 1960 | D | 7,064 | 4,648 | 11,721 | |
| 1956 | R | 5,085 | 5,816 | 10,913 | |
| 1952 | R | 4,139 | 7,473 | 11,628 | |
| 1948 | D | 5,711 | 3,974 | 9,786 | |
| 1944 | R | 4,799 | 4,833 | 9,659 | |
| 1940 | D | 5,526 | 5,376 | 10,923 | |
| 1936 | D | 6,285 | 3,259 | 10,503 | |
| 1932 | D | 7,174 | 2,265 | 9,499 | |
| 1928 | D | 6,134 | 4,014 | 10,169 | |
| 1924 | R | 1,994 | 3,590 | 8,744 | |
| 1920 | R | 2,174 | 6,320 | 8,671 | |
| 1916 | R | 2,085 | 2,408 | 4,535 | |
| 1912 | D | 2,326 | 664 | 4,282 | |
| 1908 | D | 2,510 | 1,865 | 4,448 | |
| 1904 | R | 2,040 | 2,290 | 4,471 | |
| 1900 | D | 2,434 | 2,224 | 4,698 | |
| 1896 | D | 2,417 | 2,066 | 4,524 | |
| 1892 | D | 2,375 | 1,592 | 4,082 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Carroll County's farming communities have shifted decisively Republican over the past decade, with the 2024 presidential margin exceeding 40 points — a pattern consistent with broader rural Iowa realignment away from its historically competitive roots.
The Republican margin in Carroll County reached its widest at forty-eight points in 1920. The margin in 2024 was forty-two points, in line with the county's deep historical pattern.
Carroll County's loyalty is rooted in its place. Median household income of $72,930, a 93% non-Hispanic-white share, and a population of 20,594 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 Hardin County and Audubon County.
