| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 690 | 896 | 1,614 | |
| 2020 | R | 672 | 862 | 1,557 | |
| 2016 | R | 527 | 814 | 1,434 | |
| 2012 | R | 582 | 774 | 1,392 | |
| 2008 | R | 610 | 756 | 1,410 | |
| 2004 | R | 630 | 781 | 1,439 | |
| 2000 | R | 540 | 740 | 1,343 | |
| 1996 | D | 572 | 491 | 1,242 | |
| 1992 | D | 582 | 378 | 1,173 | |
| 1988 | D | 631 | 536 | 1,170 | |
| 1984 | D | 628 | 599 | 1,227 | |
| 1980 | R | 570 | 583 | 1,260 | |
| 1976 | D | 658 | 606 | 1,271 | |
| 1972 | R | 456 | 715 | 1,182 | |
| 1968 | D | 602 | 525 | 1,194 | |
| 1964 | D | 860 | 374 | 1,235 | |
| 1960 | R | 655 | 684 | 1,343 | |
| 1956 | R | 689 | 834 | 1,523 | |
| 1952 | R | 747 | 801 | 1,559 | |
| 1948 | R | 647 | 814 | 1,625 | |
| 1944 | D | 965 | 866 | 1,837 | |
| 1940 | R | 967 | 1,080 | 2,060 | |
| 1936 | R | 1,060 | 1,070 | 2,154 | |
| 1932 | R | 527 | 1,454 | 2,007 | |
| 1928 | R | 360 | 1,305 | 1,704 | |
| 1924 | R | 50 | 1,421 | 1,559 | |
| 1920 | R | 89 | 1,272 | 1,411 | |
| 1916 | R | 194 | 860 | 1,103 | |
| 1912 | R | 59 | 495 | 1,105 | |
| 1908 | R | 63 | 1,026 | 1,133 | |
| 1904 | R | 29 | 659 | 697 | |
| 1900 | R | 31 | 452 | 490 | |
| 1896 | R | 45 | 411 | 462 | |
| 1892 | R | 202 | 400 | 612 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Keweenaw's tiny, geographically isolated population — spread across a former copper-mining peninsula jutting into Lake Superior — has shifted steadily toward Republican margins over the past decade, reaching R+12.8 in 2024.
The Republican margin in Keweenaw County reached its widest at ninety points in 1904. The margin in 2024 was thirteen points, in line with the county's deep historical pattern.
Keweenaw County's loyalty is rooted in its place. Median household income of $52,583, a 93% non-Hispanic-white share, and a population of 2,133 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 Greene County and Caldwell County.
