| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 2,206 | 8,176 | 10,475 | |
| 2020 | R | 2,654 | 8,407 | 11,201 | |
| 2016 | R | 2,691 | 7,972 | 10,894 | |
| 2012 | R | 3,075 | 7,561 | 10,766 | |
| 2008 | R | 3,103 | 7,619 | 10,868 | |
| 2004 | R | 3,089 | 7,457 | 10,718 | |
| 2000 | R | 3,205 | 5,772 | 9,343 | |
| 1996 | R | 4,260 | 4,418 | 9,543 | |
| 1992 | R | 4,005 | 4,434 | 10,069 | |
| 1988 | R | 3,210 | 5,900 | 9,369 | |
| 1984 | R | 2,916 | 6,585 | 9,723 | |
| 1980 | R | 3,841 | 5,130 | 9,198 | |
| 1976 | R | 3,600 | 4,139 | 7,905 | |
| 1972 | R | 1,465 | 4,322 | 6,157 | |
| 1968 | D | 1,336 | 1,113 | 6,746 | |
| 1964 | D | 4,534 | 1,155 | 5,689 | |
| 1960 | R | 1,034 | 2,017 | 4,063 | |
| 1956 | R | 878 | 1,384 | 3,418 | |
| 1952 | D | 2,055 | 1,894 | 3,949 | |
| 1948 | D | 724 | 259 | 2,856 | |
| 1944 | D | 1,765 | 803 | 2,568 | |
| 1940 | D | 2,842 | 371 | 3,213 | |
| 1936 | D | 1,778 | 272 | 2,050 | |
| 1932 | D | 2,285 | 58 | 2,343 | |
| 1928 | D | 1,085 | 422 | 1,509 | |
| 1924 | D | 875 | 7 | 883 | |
| 1920 | D | 1,221 | 98 | 1,319 | |
| 1916 | D | 1,106 | 22 | 1,129 | |
| 1912 | D | 696 | 11 | 794 | |
| 1908 | D | 634 | 53 | 711 | |
| 1904 | D | 496 | 15 | 512 | |
| 1900 | D | 750 | 105 | 855 | |
| 1896 | D | 1,586 | 86 | 1,697 | |
| 1892 | D | 1,216 | 836 | 2,052 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
A rural north Louisiana parish where timber and agriculture define the economy, Union recorded an R+57 margin in 2024 — among the most one-sided results in the state and a signal of how thoroughly small rural parishes have shifted over the past two decades.
The unraveling was not abrupt. The Democratic margin in Union Parish peaked at ninety-eight points in 1924; it narrowed steadily over the late twentieth century. The 1972 election delivered the county to the Republican party for the first time in many years, by a margin of forty-six points. By 2024, the margin had widened further.
The economic and demographic context is severe. Union Parish's median household income of $42,885 is among the lowest of any county in the United States; 29% of residents live below the federal poverty line. The county's voting pattern over the last decade is most similar to that of Tattnall County and Bradford County.