| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 761 | 3,109 | 3,917 | |
| 2020 | R | 822 | 2,955 | 3,849 | |
| 2016 | R | 749 | 2,443 | 3,338 | |
| 2012 | R | 1,238 | 1,758 | 3,061 | |
| 2008 | R | 1,278 | 1,840 | 3,193 | |
| 2004 | R | 1,188 | 1,869 | 3,073 | |
| 2000 | R | 1,049 | 1,345 | 2,459 | |
| 1996 | D | 1,189 | 838 | 2,346 | |
| 1992 | D | 1,171 | 699 | 2,329 | |
| 1988 | D | 1,060 | 881 | 1,952 | |
| 1984 | D | 1,042 | 1,042 | 2,093 | |
| 1980 | D | 988 | 684 | 1,704 | |
| 1976 | D | 1,164 | 436 | 1,623 | |
| 1972 | R | 612 | 719 | 1,347 | |
| 1968 | D | 685 | 413 | 1,407 | |
| 1964 | D | 1,246 | 267 | 1,517 | |
| 1960 | D | 1,028 | 756 | 1,784 | |
| 1956 | D | 1,223 | 547 | 1,771 | |
| 1952 | D | 1,383 | 465 | 1,851 | |
| 1948 | D | 1,381 | 342 | 1,731 | |
| 1944 | D | 1,360 | 516 | 1,888 | |
| 1940 | D | 1,473 | 495 | 1,972 | |
| 1936 | D | 1,456 | 404 | 1,875 | |
| 1932 | D | 1,792 | 365 | 2,163 | |
| 1928 | R | 823 | 1,010 | 1,835 | |
| 1924 | D | 1,007 | 750 | 1,780 | |
| 1920 | D | 1,782 | 536 | 2,327 | |
| 1916 | D | 1,060 | 283 | 1,347 | |
| 1912 | D | 906 | 174 | 1,194 | |
| 1908 | D | 958 | 321 | 1,288 | |
| 1904 | D | 941 | 334 | 1,291 | |
| 1900 | D | 1,018 | 404 | 1,429 | |
| 1896 | D | 933 | 396 | 1,345 | |
| 1892 | D | 737 | 237 | 999 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Gallatin County, tucked along the Ohio River with fewer than 8,000 residents, delivered a 59.9-point Republican margin in 2024 — a figure typical of rural river counties that have shifted sharply rightward over the past two decades.
The unraveling was not abrupt. The Democratic margin in Gallatin County peaked at sixty-six points in 1932; it narrowed steadily over the late twentieth century. The 2000 election delivered the county to the Republican party for the first time in many years, by a margin of twelve points. By 2024, the margin had widened further.
The economic and demographic context is severe. Gallatin County's median household income of $63,346 is among the lowest of any county in the United States; 14% of residents live below the federal poverty line. The county's voting pattern over the last decade is most similar to that of Isanti County and Lewis County.