| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 9,702 | 31,115 | 41,327 | |
| 2020 | R | 11,198 | 34,339 | 46,240 | |
| 2016 | R | 10,665 | 31,902 | 43,896 | |
| 2012 | R | 12,074 | 29,503 | 42,341 | |
| 2008 | R | 11,581 | 28,210 | 40,696 | |
| 2004 | R | 13,684 | 26,358 | 40,574 | |
| 2000 | R | 14,414 | 21,314 | 36,675 | |
| 1996 | D | 18,550 | 13,944 | 36,361 | |
| 1992 | R | 13,325 | 14,662 | 34,664 | |
| 1988 | R | 12,686 | 18,745 | 32,212 | |
| 1984 | R | 9,640 | 23,696 | 34,089 | |
| 1980 | R | 10,804 | 16,644 | 28,681 | |
| 1976 | R | 10,627 | 12,895 | 24,282 | |
| 1972 | R | 4,415 | 13,753 | 19,182 | |
| 1968 | R | 4,627 | 5,214 | 18,677 | |
| 1964 | R | 6,729 | 8,577 | 15,306 | |
| 1960 | D | 8,992 | 3,126 | 13,210 | |
| 1956 | R | 2,460 | 4,983 | 7,684 | |
| 1952 | D | 4,252 | 3,848 | 8,100 | |
| 1948 | D | 1,262 | 1,048 | 4,334 | |
| 1944 | D | 3,539 | 550 | 4,089 | |
| 1940 | D | 3,217 | 601 | 3,818 | |
| 1936 | D | 1,894 | 526 | 2,420 | |
| 1932 | D | 2,126 | 215 | 2,341 | |
| 1928 | D | 1,642 | 268 | 1,910 | |
| 1924 | D | 482 | 415 | 897 | |
| 1920 | R | 477 | 713 | 1,190 | |
| 1916 | D | 606 | 113 | 1,307 | |
| 1912 | D | 455 | 89 | 822 | |
| 1908 | D | 634 | 372 | 1,013 | |
| 1904 | D | 702 | 144 | 851 | |
| 1900 | D | 740 | 490 | 1,230 | |
| 1896 | D | 597 | 348 | 961 | |
| 1892 | D | 1,210 | 579 | 1,789 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Terrebonne Parish sits at the edge of Louisiana's disappearing coastal wetlands, and its economy—tied to offshore energy and commercial fishing—has tracked with a steady rightward shift over the past two decades, producing one of the state's wider presidential margins in 2024.
The unraveling was not abrupt. The Democratic margin in Terrebonne Parish peaked at eighty-two 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 nineteen points. By 2024, the margin had widened further.
The economic and demographic context is severe. Terrebonne Parish's median household income of $64,836 is among the lowest of any county in the United States; 16% of residents live below the federal poverty line. The county's voting pattern over the last decade is most similar to that of Vernon Parish and Tangipahoa Parish.