| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | D | 33,165 | 11,711 | 45,471 | |
| 2020 | D | 31,244 | 13,012 | 44,686 | |
| 2016 | D | 23,255 | 13,478 | 38,087 | |
| 2012 | D | 22,023 | 15,716 | 38,156 | |
| 2008 | D | 20,526 | 16,921 | 37,706 | |
| 2004 | R | 12,136 | 18,856 | 31,206 | |
| 2000 | R | 8,295 | 15,440 | 24,649 | |
| 1996 | R | 7,656 | 13,006 | 22,696 | |
| 1992 | R | 7,003 | 11,945 | 22,690 | |
| 1988 | R | 4,330 | 12,413 | 16,826 | |
| 1984 | R | 3,291 | 10,121 | 13,412 | |
| 1980 | R | 4,395 | 5,300 | 10,067 | |
| 1976 | D | 4,640 | 2,974 | 7,614 | |
| 1972 | R | 791 | 3,560 | 4,351 | |
| 1968 | D | 1,213 | 1,195 | 4,623 | |
| 1964 | D | 1,972 | 1,503 | 3,475 | |
| 1960 | D | 1,765 | 496 | 2,261 | |
| 1956 | D | 1,779 | 484 | 2,263 | |
| 1952 | D | 1,665 | 321 | 1,986 | |
| 1948 | D | 1,209 | 126 | 1,481 | |
| 1944 | D | 946 | 96 | 1,042 | |
| 1940 | D | 1,291 | 86 | 1,380 | |
| 1936 | D | 837 | 73 | 911 | |
| 1932 | D | 461 | 18 | 483 | |
| 1928 | D | 472 | 156 | 628 | |
| 1924 | D | 382 | 24 | 434 | |
| 1920 | D | 488 | 201 | 689 | |
| 1916 | D | 490 | 73 | 619 | |
| 1912 | D | 434 | 11 | 506 | |
| 1908 | D | 352 | 172 | 612 | |
| 1904 | D | 434 | 133 | 693 | |
| 1900 | D | 393 | 184 | 631 | |
| 1896 | R | 473 | 483 | 966 | |
| 1892 | D | 532 | 390 | 1,123 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Rockdale County, a small exurban county southeast of Atlanta with around 70,000 residents, returned a 47.5-point Democratic margin in 2024, reflecting the rapid demographic shift toward majority-minority composition that has reshaped the Atlanta metro's outer ring.
The unraveling was not abrupt. The Democratic margin in Rockdale County peaked at ninety-two points in 1932; it narrowed steadily over the late twentieth century. The 2008 election delivered the county to the Republican party for the first time in many years, by a margin of ten points. By 2024, the margin had widened further.
The economic and demographic context is severe. Rockdale County's median household income of $77,247 is among the lowest of any county in the United States; 11% of residents live below the federal poverty line. The county's voting pattern over the last decade is most similar to that of Harrisonburg city and Hamilton County.
