| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 1,000 | 1,876 | 2,932 | |
| 2020 | R | 1,052 | 1,869 | 2,964 | |
| 2016 | R | 974 | 1,627 | 2,747 | |
| 2012 | D | 1,497 | 1,320 | 2,873 | |
| 2008 | D | 1,785 | 1,372 | 3,205 | |
| 2004 | D | 1,817 | 1,671 | 3,540 | |
| 2000 | D | 1,623 | 1,492 | 3,197 | |
| 1996 | D | 1,840 | 1,282 | 3,533 | |
| 1992 | D | 1,578 | 1,161 | 3,725 | |
| 1988 | D | 2,137 | 1,616 | 3,774 | |
| 1984 | R | 1,932 | 2,150 | 4,101 | |
| 1980 | R | 1,720 | 2,507 | 4,543 | |
| 1976 | D | 2,610 | 1,617 | 4,257 | |
| 1972 | D | 2,719 | 1,971 | 4,699 | |
| 1968 | D | 2,463 | 2,062 | 4,707 | |
| 1964 | D | 3,235 | 1,914 | 5,149 | |
| 1960 | D | 2,835 | 2,626 | 5,461 | |
| 1956 | D | 2,971 | 2,652 | 5,623 | |
| 1952 | R | 2,351 | 3,648 | 5,999 | |
| 1948 | D | 3,146 | 2,438 | 5,681 | |
| 1944 | R | 2,487 | 2,593 | 5,080 | |
| 1940 | D | 3,297 | 3,277 | 6,574 | |
| 1936 | D | 3,335 | 2,113 | 5,729 | |
| 1932 | D | 3,910 | 1,983 | 6,191 | |
| 1928 | R | 2,642 | 3,180 | 5,865 | |
| 1924 | R | 308 | 2,193 | 3,975 | |
| 1920 | R | 436 | 2,739 | 4,579 | |
| 1916 | D | 1,758 | 907 | 2,872 | |
| 1912 | D | 787 | 0 | 2,331 | |
| 1908 | R | 813 | 1,616 | 2,729 | |
| 1904 | R | 383 | 2,077 | 2,826 | |
| 1900 | R | 1,092 | 1,558 | 2,764 | |
| 1896 | D | 1,230 | 1,171 | 2,436 | |
| 1892 | R | 362 | 752 | 1,932 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Day County's population has contracted by roughly a third since 1980, leaving an older, rural electorate concentrated in Webster that has shifted decisively toward Republican presidential candidates over the past two decades.
The Republican margin in Day County reached its widest at sixty points in 1904. The margin in 2024 was thirty points, in line with the county's deep historical pattern.
Day County's loyalty is rooted in its place. Median household income of $66,033, a 84% non-Hispanic-white share, and a population of 5,437 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 Buffalo County and Mitchell County.
