| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 1,393 | 3,431 | 4,900 | |
| 2020 | R | 1,626 | 3,422 | 5,130 | |
| 2016 | R | 1,493 | 3,163 | 5,046 | |
| 2012 | R | 2,266 | 2,823 | 5,186 | |
| 2008 | D | 2,575 | 2,501 | 5,148 | |
| 2004 | R | 2,340 | 3,128 | 5,521 | |
| 2000 | R | 2,122 | 2,657 | 4,938 | |
| 1996 | D | 2,232 | 2,054 | 4,733 | |
| 1992 | R | 2,049 | 2,137 | 5,266 | |
| 1988 | D | 2,594 | 2,320 | 4,951 | |
| 1984 | R | 2,349 | 3,129 | 5,545 | |
| 1980 | R | 1,920 | 3,290 | 5,682 | |
| 1976 | R | 2,682 | 3,056 | 5,843 | |
| 1972 | R | 1,986 | 3,643 | 5,786 | |
| 1968 | R | 1,777 | 3,604 | 5,677 | |
| 1964 | D | 3,582 | 2,452 | 6,061 | |
| 1960 | R | 2,476 | 4,514 | 6,996 | |
| 1956 | R | 2,513 | 4,563 | 7,084 | |
| 1952 | R | 1,941 | 5,432 | 7,470 | |
| 1948 | D | 2,871 | 2,716 | 6,021 | |
| 1944 | R | 2,851 | 3,150 | 6,062 | |
| 1940 | R | 3,540 | 3,623 | 7,310 | |
| 1936 | D | 3,993 | 2,530 | 6,705 | |
| 1932 | D | 3,782 | 2,013 | 6,110 | |
| 1928 | R | 1,688 | 3,424 | 5,224 | |
| 1924 | R | 360 | 3,064 | 5,216 | |
| 1920 | R | 601 | 4,397 | 5,109 | |
| 1916 | R | 691 | 2,464 | 3,190 | |
| 1912 | R | 694 | 773 | 3,066 | |
| 1908 | R | 737 | 2,154 | 2,950 | |
| 1904 | R | 531 | 2,346 | 2,946 | |
| 1900 | R | 748 | 2,537 | 3,322 | |
| 1896 | R | 894 | 2,439 | 3,361 | |
| 1892 | R | 1,064 | 1,771 | 2,870 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Franklin County's R+41.6 margin in 2024 reflects the broader consolidation of rural north-central Iowa around Republican candidates, a shift that has deepened consistently over the past three presidential cycles.
The Democratic margin in Franklin County peaked at twenty-nine points in 1932. By 2012 the county had flipped, voting Republican for the first time in many years. The 2024 margin was forty-two points, the most Republican-leaning result in the county's modern history.
The economic context is the key. Franklin County's median household income of $59,894 sits well below state and national norms, and 14% of residents live below the federal poverty line. The shift here is part of a broader realignment of working-class places across the country. The county's voting pattern over the last decade is most similar to that of Nobles County and Iowa County.