| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 34,585 | 36,589 | 72,886 | |
| 2020 | D | 34,902 | 34,721 | 72,615 | |
| 2016 | R | 29,302 | 31,675 | 66,208 | |
| 2012 | D | 35,068 | 26,519 | 63,497 | |
| 2008 | D | 37,238 | 27,482 | 65,986 | |
| 2004 | D | 35,616 | 29,761 | 66,772 | |
| 2000 | D | 31,198 | 23,967 | 58,907 | |
| 1996 | D | 30,257 | 15,403 | 55,654 | |
| 1992 | D | 25,125 | 17,135 | 63,921 | |
| 1988 | R | 23,578 | 27,734 | 51,745 | |
| 1984 | R | 21,183 | 31,753 | 53,191 | |
| 1980 | R | 20,943 | 21,517 | 49,077 | |
| 1976 | D | 23,473 | 22,534 | 47,407 | |
| 1972 | R | 16,379 | 24,617 | 41,035 | |
| 1968 | D | 21,752 | 16,009 | 38,292 | |
| 1964 | D | 24,813 | 11,307 | 36,143 | |
| 1960 | R | 18,252 | 21,699 | 39,951 | |
| 1956 | R | 11,483 | 23,028 | 34,511 | |
| 1952 | R | 12,113 | 21,207 | 33,351 | |
| 1948 | R | 11,163 | 13,923 | 25,260 | |
| 1944 | R | 14,070 | 14,335 | 28,430 | |
| 1940 | D | 15,861 | 14,877 | 30,765 | |
| 1936 | R | 11,268 | 14,987 | 27,081 | |
| 1932 | R | 12,110 | 14,451 | 26,797 | |
| 1928 | R | 8,226 | 15,541 | 23,859 | |
| 1924 | R | 4,184 | 13,122 | 18,159 | |
| 1920 | R | 5,466 | 12,333 | 17,973 | |
| 1916 | R | 5,527 | 6,731 | 12,531 | |
| 1912 | D | 4,397 | 1,782 | 11,726 | |
| 1908 | R | 2,871 | 6,133 | 9,294 | |
| 1904 | R | 2,333 | 5,765 | 8,394 | |
| 1900 | R | 3,410 | 6,228 | 9,949 | |
| 1896 | R | 2,817 | 7,889 | 11,003 | |
| 1892 | R | 4,094 | 6,165 | 10,765 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Home to Augusta, Maine's capital, Kennebec County blends state-government employment with rural and small-town voters, producing margins close enough to make it a reliable indicator of statewide competitive pressure.
The Democratic margin in Kennebec County has rarely exceeded thirty-seven points in modern history; the Republican margin has rarely exceeded forty-nine points. 2024 delivered the county to the Republican candidate by three points.
Kennebec County's demographics resemble the country more than they resemble most counties. A 92% non-Hispanic-white share, a 12% poverty rate, and a median household income of $69,077 — all within the broad national range. The county's voting pattern over the last decade is most similar to that of Androscoggin County and Franklin County.
