| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 1,132 | 5,682 | 6,881 | |
| 2020 | R | 1,261 | 5,190 | 6,557 | |
| 2016 | R | 1,127 | 4,007 | 5,314 | |
| 2012 | R | 1,564 | 3,309 | 4,973 | |
| 2008 | R | 2,011 | 3,322 | 5,457 | |
| 2004 | R | 2,515 | 2,931 | 5,481 | |
| 2000 | D | 2,697 | 1,924 | 4,697 | |
| 1996 | D | 2,318 | 1,468 | 4,185 | |
| 1992 | D | 2,593 | 1,229 | 4,331 | |
| 1988 | D | 1,726 | 1,604 | 3,348 | |
| 1984 | D | 1,846 | 1,669 | 3,560 | |
| 1980 | D | 2,351 | 1,403 | 3,817 | |
| 1976 | D | 2,463 | 908 | 3,399 | |
| 1972 | R | 911 | 1,615 | 2,589 | |
| 1968 | D | 809 | 780 | 3,053 | |
| 1964 | D | 2,190 | 746 | 2,936 | |
| 1960 | D | 1,275 | 1,195 | 2,487 | |
| 1956 | D | 1,547 | 919 | 2,475 | |
| 1952 | D | 1,491 | 930 | 2,449 | |
| 1948 | D | 1,408 | 558 | 2,127 | |
| 1944 | D | 1,002 | 627 | 1,630 | |
| 1940 | D | 1,699 | 638 | 2,358 | |
| 1936 | D | 1,166 | 498 | 1,670 | |
| 1932 | D | 1,207 | 360 | 1,575 | |
| 1928 | D | 622 | 588 | 1,210 | |
| 1924 | D | 581 | 285 | 878 | |
| 1920 | D | 770 | 687 | 1,457 | |
| 1916 | D | 936 | 456 | 1,392 | |
| 1912 | D | 1,184 | 631 | 1,870 | |
| 1908 | D | 904 | 672 | 1,581 | |
| 1904 | D | 1,014 | 614 | 1,630 | |
| 1900 | D | 1,213 | 775 | 1,990 | |
| 1896 | D | 1,276 | 778 | 2,064 | |
| 1892 | D | 1,092 | 514 | 1,673 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Cannon County's 2024 presidential margin of R+66.1 points places it among Tennessee's most lopsided rural counties, reflecting a demographic profile dominated by small towns and farmland with little of the suburban growth reshaping nearby Middle Tennessee.
The unraveling was not abrupt. The Democratic margin in Cannon County peaked at fifty-four points in 1932; it narrowed steadily over the late twentieth century. The 2004 election delivered the county to the Republican party for the first time in many years, by a margin of eight points. By 2024, the margin had widened further.
The economic and demographic context is severe. Cannon County's median household income of $59,443 is among the lowest of any county in the United States; 18% of residents live below the federal poverty line. The county's voting pattern over the last decade is most similar to that of Giles County and Warren County.
