| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 1,438 | 3,712 | 5,241 | |
| 2020 | R | 1,615 | 3,625 | 5,326 | |
| 2016 | R | 1,621 | 3,216 | 5,124 | |
| 2012 | R | 2,053 | 2,707 | 4,878 | |
| 2008 | D | 2,690 | 2,617 | 5,408 | |
| 2004 | R | 2,492 | 3,163 | 5,700 | |
| 2000 | R | 2,789 | 2,968 | 5,899 | |
| 1996 | D | 2,834 | 2,214 | 5,667 | |
| 1992 | D | 3,200 | 2,162 | 6,447 | |
| 1988 | D | 3,316 | 2,916 | 6,267 | |
| 1984 | R | 2,937 | 3,435 | 6,399 | |
| 1980 | R | 2,543 | 3,965 | 6,770 | |
| 1976 | D | 3,589 | 3,524 | 7,144 | |
| 1972 | R | 2,803 | 4,414 | 7,219 | |
| 1968 | R | 3,302 | 3,411 | 7,139 | |
| 1964 | D | 4,424 | 2,836 | 7,260 | |
| 1960 | R | 3,692 | 4,015 | 7,715 | |
| 1956 | R | 3,368 | 4,125 | 7,504 | |
| 1952 | R | 3,405 | 4,152 | 7,565 | |
| 1948 | D | 3,776 | 3,391 | 7,217 | |
| 1944 | D | 3,909 | 3,641 | 7,585 | |
| 1940 | D | 4,854 | 4,490 | 9,416 | |
| 1936 | D | 5,786 | 3,209 | 9,090 | |
| 1932 | D | 5,669 | 2,745 | 8,507 | |
| 1928 | R | 3,461 | 4,009 | 7,494 | |
| 1924 | R | 2,909 | 3,139 | 7,613 | |
| 1920 | R | 2,861 | 3,956 | 7,318 | |
| 1916 | D | 4,485 | 3,193 | 8,066 | |
| 1912 | D | 2,223 | 719 | 4,195 | |
| 1908 | D | 2,434 | 1,878 | 4,423 | |
| 1904 | D | 1,906 | 1,827 | 3,904 | |
| 1900 | D | 2,626 | 1,846 | 4,533 | |
| 1896 | D | 2,470 | 1,946 | 4,464 | |
| 1892 | D | 2,203 | 1,533 | 3,936 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Cass County's small population and deep rural character have pushed its presidential margins steadily rightward over the past decade, reaching R+43.4 in 2024 — among the widest gaps in a state where statewide results trend the opposite direction.
The Democratic margin in Cass County peaked at thirty-six points in 1912. By 2012 the county had flipped, voting Republican for the first time in many years. The 2024 margin was forty-three points, the most Republican-leaning result in the county's modern history.
The economic context is the key. Cass County's median household income of $68,125 sits well below state and national norms, and 11% 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 Vermilion County and Crawford County.