| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | D | 23,425 | 21,215 | 45,170 | |
| 2020 | D | 27,379 | 21,000 | 48,920 | |
| 2016 | D | 24,047 | 18,745 | 44,086 | |
| 2012 | D | 27,589 | 19,274 | 47,309 | |
| 2008 | D | 25,431 | 18,581 | 44,358 | |
| 2004 | D | 18,695 | 18,074 | 37,003 | |
| 2000 | R | 14,365 | 15,915 | 30,672 | |
| 1996 | D | 12,198 | 12,080 | 25,392 | |
| 1992 | R | 11,852 | 12,576 | 26,596 | |
| 1988 | R | 9,502 | 13,161 | 22,801 | |
| 1984 | R | 9,566 | 12,909 | 22,590 | |
| 1980 | R | 9,205 | 10,557 | 20,126 | |
| 1976 | D | 10,471 | 9,332 | 19,912 | |
| 1972 | R | 5,801 | 10,892 | 16,800 | |
| 1968 | D | 6,103 | 5,451 | 16,308 | |
| 1964 | R | 3,775 | 7,729 | 11,504 | |
| 1960 | R | 2,616 | 4,633 | 7,249 | |
| 1956 | R | 937 | 1,356 | 6,034 | |
| 1952 | R | 2,014 | 4,726 | 6,740 | |
| 1948 | D | 605 | 154 | 3,477 | |
| 1944 | D | 2,111 | 73 | 2,401 | |
| 1940 | — | 0 | 0 | 0 | |
| 1936 | D | 2,062 | 0 | 2,120 | |
| 1932 | D | 1,809 | 0 | 1,876 | |
| 1928 | D | 1,202 | 174 | 1,376 | |
| 1924 | D | 1,136 | 18 | 1,216 | |
| 1920 | D | 1,150 | 194 | 1,344 | |
| 1916 | D | 1,357 | 142 | 1,520 | |
| 1912 | D | 910 | 0 | 993 | |
| 1908 | D | 1,228 | 173 | 1,409 | |
| 1904 | D | 919 | 137 | 1,056 | |
| 1900 | D | 1,199 | 150 | 1,349 | |
| 1896 | D | 1,550 | 326 | 1,900 | |
| 1892 | D | 1,535 | 639 | 2,182 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Sumter County's population is roughly 55% Black, anchoring a modest but durable Democratic lean in presidential races — its 2024 margin of D+4.9 reflects a district where turnout patterns and demographic shifts shape every close contest.
The Democratic margin in Sumter County reached its widest at ninety-seven points in 1936. The margin in 2024 was five points — still decisive.
Sumter County's loyalty is rooted in its place. Median household income of $56,693, a 45% non-Hispanic-white share, and a population of 104,725 together describe a community whose political habits are deeply settled. The county's voting pattern over the last decade is most similar to that of Danville city and Prince Edward County.
