| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 63,976 | 95,867 | 162,046 | |
| 2020 | R | 62,228 | 90,433 | 154,984 | |
| 2016 | R | 43,200 | 72,791 | 121,181 | |
| 2012 | R | 34,421 | 70,862 | 106,739 | |
| 2008 | R | 36,480 | 67,515 | 104,940 | |
| 2004 | R | 28,904 | 63,662 | 93,248 | |
| 2000 | R | 24,883 | 53,445 | 80,019 | |
| 1996 | R | 22,959 | 36,392 | 65,638 | |
| 1992 | R | 21,861 | 30,384 | 71,467 | |
| 1988 | R | 23,436 | 34,028 | 59,081 | |
| 1984 | R | 18,609 | 39,166 | 58,009 | |
| 1980 | R | 18,253 | 27,614 | 47,544 | |
| 1976 | D | 21,711 | 19,475 | 41,744 | |
| 1972 | R | 11,350 | 21,045 | 32,432 | |
| 1968 | D | 11,439 | 10,631 | 30,103 | |
| 1964 | D | 15,917 | 8,477 | 24,497 | |
| 1960 | R | 10,561 | 10,880 | 21,705 | |
| 1956 | R | 7,137 | 9,536 | 16,881 | |
| 1952 | D | 8,386 | 8,360 | 16,761 | |
| 1948 | D | 4,783 | 2,133 | 8,363 | |
| 1944 | D | 5,543 | 850 | 7,691 | |
| 1940 | D | 3,781 | 799 | 4,585 | |
| 1936 | D | 2,284 | 462 | 2,785 | |
| 1932 | D | 2,948 | 617 | 3,576 | |
| 1928 | R | 1,086 | 1,588 | 2,674 | |
| 1924 | D | 1,761 | 1,114 | 2,994 | |
| 1920 | R | 1,184 | 1,235 | 2,605 | |
| 1916 | D | 1,033 | 581 | 1,728 | |
| 1912 | D | 746 | 263 | 1,383 | |
| 1908 | — | — | — | — | |
| 1904 | — | — | — | — | |
| 1900 | — | — | — | — | |
| 1896 | — | — | — | — | |
| 1892 | — | — | — | — | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Brazoria County's economy anchors on the Gulf Coast petrochemical industry, and its electorate has shifted roughly 15 points toward Republican presidential candidates over the past four cycles, outpacing the statewide trend.
The shift began with civil rights. 1980 marked the realignment in Brazoria County, by a twenty points margin. The Republican margin reached its widest at thirty-seven points in 2004. The 2024 margin was twenty points.
The political shift has tracked, in Brazoria County, the political shift of the South more broadly. A 48% non-Hispanic-white share, a median household income of $97,993, and a 7% poverty rate describe the demographic context. The county's voting pattern over the last decade is most similar to that of Guadalupe County and Forsyth County.