| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 8,698 | 23,112 | 32,277 | |
| 2020 | R | 8,589 | 22,340 | 31,398 | |
| 2016 | R | 8,171 | 19,131 | 29,278 | |
| 2012 | R | 10,470 | 17,266 | 28,692 | |
| 2008 | R | 11,014 | 16,640 | 28,285 | |
| 2004 | R | 9,820 | 17,068 | 27,045 | |
| 2000 | R | 7,133 | 13,393 | 21,260 | |
| 1996 | R | 7,562 | 10,159 | 20,068 | |
| 1992 | R | 7,259 | 9,044 | 21,745 | |
| 1988 | R | 6,882 | 12,180 | 19,200 | |
| 1984 | R | 5,730 | 14,062 | 19,901 | |
| 1980 | R | 6,586 | 10,384 | 18,195 | |
| 1976 | R | 7,361 | 9,290 | 17,081 | |
| 1972 | R | 5,370 | 10,705 | 16,739 | |
| 1968 | R | 5,725 | 9,072 | 16,492 | |
| 1964 | D | 11,222 | 7,258 | 18,480 | |
| 1960 | R | 6,565 | 12,711 | 19,276 | |
| 1956 | R | 4,958 | 12,347 | 17,305 | |
| 1952 | R | 5,694 | 12,705 | 18,399 | |
| 1948 | R | 6,120 | 8,607 | 14,755 | |
| 1944 | R | 5,573 | 9,963 | 15,536 | |
| 1940 | R | 7,081 | 10,303 | 17,384 | |
| 1936 | D | 8,315 | 7,956 | 16,641 | |
| 1932 | R | 7,008 | 8,272 | 15,486 | |
| 1928 | R | 3,601 | 10,028 | 13,724 | |
| 1924 | R | 4,721 | 7,519 | 13,093 | |
| 1920 | R | 6,361 | 8,178 | 14,610 | |
| 1916 | D | 4,578 | 3,646 | 8,383 | |
| 1912 | D | 3,632 | 2,530 | 7,894 | |
| 1908 | R | 4,233 | 4,318 | 8,796 | |
| 1904 | R | 3,036 | 4,235 | 7,540 | |
| 1900 | R | 3,797 | 4,011 | 7,933 | |
| 1896 | D | 4,062 | 3,762 | 7,884 | |
| 1892 | D | 3,489 | 3,347 | 7,280 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Knox County's rolling farmland and small-town core around Mount Vernon have produced Republican presidential margins exceeding 40 points in recent cycles, reflecting a broader rural realignment that has deepened steadily since 2008.
The Republican margin in Knox County reached its widest at forty-seven points in 1928. The margin in 2024 was forty-five points, in line with the county's deep historical pattern.
Knox County's loyalty is rooted in its place. Median household income of $73,878, a 94% non-Hispanic-white share, and a population of 63,142 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 Wayne County and Missaukee County.
