| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 4,084 | 8,102 | 12,289 | |
| 2020 | R | 4,935 | 8,183 | 13,257 | |
| 2016 | R | 4,729 | 7,061 | 12,092 | |
| 2012 | R | 5,796 | 6,584 | 12,541 | |
| 2008 | R | 5,935 | 7,449 | 13,551 | |
| 2004 | R | 5,236 | 6,592 | 11,934 | |
| 2000 | R | 4,662 | 5,768 | 10,589 | |
| 1996 | D | 5,407 | 3,855 | 10,055 | |
| 1992 | R | 4,644 | 4,647 | 10,680 | |
| 1988 | R | 4,420 | 6,019 | 10,465 | |
| 1984 | R | 4,424 | 6,331 | 10,796 | |
| 1980 | D | 6,274 | 4,035 | 10,456 | |
| 1976 | D | 6,363 | 3,463 | 9,863 | |
| 1972 | R | 2,676 | 8,337 | 11,065 | |
| 1968 | R | 2,271 | 3,011 | 9,872 | |
| 1964 | D | 3,892 | 3,815 | 7,707 | |
| 1960 | D | 5,229 | 1,980 | 7,209 | |
| 1956 | D | 3,760 | 1,252 | 5,688 | |
| 1952 | D | 5,921 | 2,094 | 8,015 | |
| 1948 | D | 1,283 | 46 | 3,419 | |
| 1944 | D | 3,041 | 33 | 3,152 | |
| 1940 | D | 3,662 | 29 | 3,691 | |
| 1936 | D | 3,458 | 0 | 3,467 | |
| 1932 | D | 3,131 | 0 | 3,147 | |
| 1928 | D | 2,460 | 74 | 2,535 | |
| 1924 | D | 1,862 | 27 | 1,896 | |
| 1920 | D | 2,162 | 16 | 2,178 | |
| 1916 | D | 1,476 | 0 | 1,489 | |
| 1912 | D | 1,609 | 0 | 1,685 | |
| 1908 | D | 1,389 | 49 | 1,438 | |
| 1904 | D | 1,593 | 58 | 1,651 | |
| 1900 | D | 1,182 | 91 | 1,273 | |
| 1896 | D | 1,379 | 158 | 1,539 | |
| 1892 | D | 1,339 | 356 | 1,751 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Union County's mill towns anchored its economy for generations, but deindustrialization reshaped both its workforce and its politics. In 2024 the county delivered a 32-point Republican presidential margin, continuing a decade-long rightward drift.
The shift began with civil rights. 2000 marked the realignment in Union County, by a ten points margin. The Republican margin reached its widest at fifty-one points in 1972. The 2024 margin was thirty-three points.
The political shift has tracked, in Union County, the political shift of the South more broadly. A 65% non-Hispanic-white share, a median household income of $41,621, and a 23% poverty rate describe the demographic context. The county's voting pattern over the last decade is most similar to that of Piscataquis County and Jefferson County.