| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 2,707 | 11,603 | 14,409 | |
| 2020 | R | 3,158 | 11,768 | 15,079 | |
| 2016 | R | 2,816 | 10,180 | 13,336 | |
| 2012 | R | 3,757 | 9,921 | 13,816 | |
| 2008 | R | 4,411 | 9,859 | 14,450 | |
| 2004 | R | 5,287 | 8,447 | 13,809 | |
| 2000 | R | 5,425 | 6,282 | 11,841 | |
| 1996 | D | 5,602 | 5,059 | 11,374 | |
| 1992 | D | 5,845 | 5,668 | 12,787 | |
| 1988 | R | 3,690 | 6,508 | 10,243 | |
| 1984 | R | 3,991 | 6,610 | 10,642 | |
| 1980 | D | 5,713 | 5,475 | 11,407 | |
| 1976 | D | 5,937 | 4,391 | 10,478 | |
| 1972 | R | 1,600 | 6,066 | 7,988 | |
| 1968 | R | 2,033 | 2,826 | 10,701 | |
| 1964 | D | 4,717 | 4,517 | 9,234 | |
| 1960 | R | 3,868 | 4,097 | 8,203 | |
| 1956 | D | 4,524 | 2,682 | 7,407 | |
| 1952 | D | 4,531 | 3,231 | 7,823 | |
| 1948 | D | 3,503 | 989 | 5,364 | |
| 1944 | D | 3,368 | 1,190 | 4,576 | |
| 1940 | D | 3,374 | 961 | 4,380 | |
| 1936 | D | 3,355 | 557 | 3,999 | |
| 1932 | D | 3,805 | 389 | 4,222 | |
| 1928 | D | 2,661 | 842 | 3,503 | |
| 1924 | D | 2,336 | 478 | 2,824 | |
| 1920 | D | 3,181 | 1,166 | 4,357 | |
| 1916 | D | 1,997 | 459 | 2,492 | |
| 1912 | D | 1,469 | 318 | 2,217 | |
| 1908 | D | 1,786 | 672 | 2,485 | |
| 1904 | D | 1,771 | 625 | 2,416 | |
| 1900 | D | 1,975 | 728 | 2,748 | |
| 1896 | D | 2,589 | 868 | 3,516 | |
| 1892 | D | 1,848 | 487 | 2,980 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Dyer County's 2024 presidential margin of R+61.8 reflects a broader shift in rural West Tennessee toward lopsided single-party results, a pattern that has accelerated over the past three election cycles.
The unraveling was not abrupt. The Democratic margin in Dyer County peaked at eighty-one 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 seven points. By 2024, the margin had widened further.
The economic and demographic context is severe. Dyer County's median household income of $58,154 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 Roane County and Calhoun County.