| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 809 | 2,917 | 3,747 | |
| 2020 | R | 980 | 3,007 | 4,002 | |
| 2016 | R | 910 | 2,622 | 3,569 | |
| 2012 | R | 1,193 | 2,469 | 3,690 | |
| 2008 | R | 1,328 | 2,342 | 3,715 | |
| 2004 | R | 1,506 | 2,235 | 3,757 | |
| 2000 | R | 1,636 | 2,116 | 3,805 | |
| 1996 | D | 1,924 | 1,296 | 3,561 | |
| 1992 | D | 1,737 | 1,243 | 3,649 | |
| 1988 | D | 2,118 | 1,946 | 4,084 | |
| 1984 | R | 1,583 | 1,937 | 3,529 | |
| 1980 | D | 1,674 | 1,397 | 3,091 | |
| 1976 | D | 1,817 | 1,047 | 2,870 | |
| 1972 | R | 753 | 1,508 | 2,268 | |
| 1968 | D | 817 | 506 | 2,460 | |
| 1964 | D | 1,173 | 760 | 1,940 | |
| 1960 | D | 1,269 | 638 | 1,962 | |
| 1956 | D | 1,086 | 900 | 1,997 | |
| 1952 | D | 1,359 | 730 | 2,089 | |
| 1948 | D | 858 | 137 | 1,265 | |
| 1944 | D | 1,176 | 102 | 1,278 | |
| 1940 | D | 1,325 | 119 | 1,444 | |
| 1936 | D | 1,054 | 64 | 1,118 | |
| 1932 | D | 1,802 | 19 | 1,821 | |
| 1928 | D | 821 | 467 | 1,288 | |
| 1924 | D | 1,475 | 78 | 1,562 | |
| 1920 | D | 658 | 121 | 1,544 | |
| 1916 | D | 682 | 18 | 752 | |
| 1912 | D | 375 | 12 | 493 | |
| 1908 | — | — | — | — | |
| 1904 | — | — | — | — | |
| 1900 | — | — | — | — | |
| 1896 | — | — | — | — | |
| 1892 | — | — | — | — | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
San Augustine sits in the forested Sabine River corridor of East Texas, where a declining rural population and long Democratic roots have given way to some of the state's most lopsided Republican presidential margins over the past decade.
The unraveling was not abrupt. The Democratic margin in San Augustine County peaked at ninety-eight points in 1932; it narrowed steadily over the late twentieth century. The 2000 election delivered the county to the Republican party for the first time in many years, by a margin of thirteen points. By 2024, the margin had widened further.
The economic and demographic context is severe. San Augustine County's median household income of $50,408 is among the lowest of any county in the United States; 27% of residents live below the federal poverty line. The county's voting pattern over the last decade is most similar to that of Graves County and Hickman County.