| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 2,464 | 4,202 | 6,786 | |
| 2020 | R | 2,659 | 4,131 | 6,922 | |
| 2016 | R | 2,306 | 3,569 | 6,363 | |
| 2012 | D | 3,451 | 2,841 | 6,458 | |
| 2008 | D | 3,649 | 2,962 | 6,802 | |
| 2004 | D | 3,662 | 3,539 | 7,309 | |
| 2000 | R | 2,903 | 3,523 | 6,879 | |
| 1996 | D | 3,472 | 2,080 | 6,730 | |
| 1992 | D | 3,474 | 1,954 | 7,465 | |
| 1988 | D | 3,867 | 2,842 | 6,780 | |
| 1984 | D | 4,238 | 3,466 | 7,742 | |
| 1980 | D | 4,181 | 3,433 | 8,250 | |
| 1976 | D | 4,846 | 2,893 | 8,007 | |
| 1972 | R | 3,396 | 3,681 | 7,230 | |
| 1968 | D | 4,697 | 2,104 | 7,116 | |
| 1964 | D | 5,878 | 1,602 | 7,491 | |
| 1960 | D | 4,578 | 3,055 | 7,656 | |
| 1956 | D | 3,695 | 2,757 | 6,468 | |
| 1952 | D | 4,078 | 2,742 | 6,851 | |
| 1948 | D | 4,968 | 1,718 | 6,968 | |
| 1944 | D | 3,981 | 1,607 | 5,639 | |
| 1940 | D | 5,219 | 2,095 | 7,353 | |
| 1936 | D | 5,065 | 1,316 | 6,513 | |
| 1932 | D | 3,148 | 1,427 | 4,974 | |
| 1928 | R | 2,110 | 2,599 | 4,843 | |
| 1924 | R | 222 | 1,536 | 4,105 | |
| 1920 | R | 859 | 1,786 | 3,230 | |
| 1916 | D | 1,089 | 474 | 1,846 | |
| 1912 | D | 638 | 239 | 1,892 | |
| 1908 | R | 420 | 826 | 1,475 | |
| 1904 | — | — | — | — | |
| 1900 | — | — | — | — | |
| 1896 | — | — | — | — | |
| 1892 | — | — | — | — | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Koochiching, anchored by International Falls on the Canadian border, was once a union-inflected timber and paper-mill community that voted competitively; by 2024 it backed the Republican ticket by more than 25 points.
The county's recent history is a story of close margins. The Democratic margin reached fifty-eight points in 1936; the Republican margin reached thirty-two points in 1924. Most other elections have been decided by single-digit points.
Koochiching County's demographics — a population of 11,833, a 90% non-Hispanic-white share, a median household income of $66,940 — situate the county close to national averages on several dimensions. The county's voting pattern over the last decade is most similar to that of Hill County and Swift County.