| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 9,441 | 9,540 | 19,417 | |
| 2020 | D | 9,622 | 9,018 | 19,125 | |
| 2016 | R | 7,886 | 8,437 | 18,097 | |
| 2012 | D | 9,652 | 8,214 | 18,357 | |
| 2008 | D | 9,887 | 7,968 | 18,245 | |
| 2004 | D | 8,797 | 8,689 | 17,741 | |
| 2000 | R | 7,041 | 7,221 | 15,327 | |
| 1996 | D | 6,772 | 5,057 | 13,842 | |
| 1992 | D | 6,055 | 5,091 | 15,039 | |
| 1988 | R | 6,786 | 6,878 | 13,779 | |
| 1984 | R | 5,789 | 7,472 | 13,349 | |
| 1980 | R | 5,400 | 6,436 | 13,622 | |
| 1976 | R | 5,777 | 6,071 | 12,245 | |
| 1972 | R | 4,680 | 6,230 | 11,069 | |
| 1968 | R | 4,244 | 4,671 | 9,234 | |
| 1964 | D | 5,121 | 3,605 | 8,736 | |
| 1960 | R | 3,961 | 5,283 | 9,255 | |
| 1956 | R | 2,636 | 5,322 | 7,966 | |
| 1952 | R | 2,584 | 5,775 | 8,398 | |
| 1948 | D | 3,663 | 3,576 | 7,325 | |
| 1944 | R | 2,321 | 4,345 | 6,702 | |
| 1940 | R | 2,832 | 4,674 | 7,537 | |
| 1936 | D | 4,136 | 2,360 | 7,003 | |
| 1932 | D | 3,960 | 2,217 | 6,328 | |
| 1928 | R | 2,466 | 3,628 | 6,136 | |
| 1924 | R | 287 | 2,518 | 5,031 | |
| 1920 | R | 556 | 4,115 | 4,931 | |
| 1916 | R | 814 | 1,288 | 2,204 | |
| 1912 | D | 929 | 525 | 2,426 | |
| 1908 | R | 832 | 1,392 | 2,348 | |
| 1904 | R | 513 | 1,677 | 2,265 | |
| 1900 | R | 858 | 1,684 | 2,626 | |
| 1896 | R | 837 | 1,803 | 2,715 | |
| 1892 | D | 1,098 | 937 | 2,302 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Nicollet County, anchored by Mankato's southern suburbs along the Minnesota River, has drifted toward competitive status over recent cycles — the 2024 presidential contest settled at roughly half a percentage point, reflecting a mixed blend of small-city and agricultural voters.
The county's recent history is a story of close margins. The Democratic margin reached twenty-eight points in 1932; the Republican margin reached seventy-two points in 1920. Most other elections have been decided by single-digit points.
Nicollet County's demographics — a population of 34,411, a 87% non-Hispanic-white share, a median household income of $79,756 — 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 Blue Earth County and Franklin County.
