| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 14,800 | 50,556 | 66,041 | |
| 2020 | R | 14,506 | 44,163 | 59,576 | |
| 2016 | R | 10,301 | 35,325 | 47,416 | |
| 2012 | R | 10,670 | 30,936 | 42,264 | |
| 2008 | R | 13,900 | 31,136 | 45,477 | |
| 2004 | R | 13,452 | 30,777 | 44,423 | |
| 2000 | R | 13,647 | 25,596 | 39,940 | |
| 1996 | R | 14,338 | 17,169 | 35,411 | |
| 1992 | D | 12,547 | 12,322 | 38,332 | |
| 1988 | R | 14,347 | 18,825 | 33,287 | |
| 1984 | R | 11,803 | 22,554 | 34,450 | |
| 1980 | R | 13,807 | 16,811 | 31,326 | |
| 1976 | D | 17,015 | 11,981 | 29,095 | |
| 1972 | R | 6,952 | 16,769 | 23,734 | |
| 1968 | D | 10,379 | 8,007 | 23,001 | |
| 1964 | D | 14,207 | 5,500 | 19,728 | |
| 1960 | D | 9,866 | 7,312 | 17,231 | |
| 1956 | D | 8,876 | 7,402 | 16,330 | |
| 1952 | D | 10,435 | 7,736 | 18,194 | |
| 1948 | D | 10,991 | 2,174 | 14,148 | |
| 1944 | D | 11,636 | 1,372 | 14,070 | |
| 1940 | D | 12,530 | 1,340 | 13,884 | |
| 1936 | D | 10,627 | 947 | 11,597 | |
| 1932 | D | 9,631 | 1,317 | 10,992 | |
| 1928 | R | 4,600 | 6,277 | 10,892 | |
| 1924 | D | 7,413 | 1,973 | 10,335 | |
| 1920 | D | 5,241 | 2,125 | 7,945 | |
| 1916 | D | 5,092 | 1,024 | 6,421 | |
| 1912 | D | 3,938 | 411 | 5,234 | |
| 1908 | — | — | — | — | |
| 1904 | — | — | — | — | |
| 1900 | — | — | — | — | |
| 1896 | — | — | — | — | |
| 1892 | — | — | — | — | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Grayson County, anchored by Sherman along the Oklahoma line, has delivered Republican presidential margins above 50 points in recent cycles, reflecting a rural-to-suburban demographic profile typical of North Texas's exurban tier.
The unraveling was not abrupt. The Democratic margin in Grayson County peaked at eighty-three points in 1936; it narrowed steadily over the late twentieth century. The 1996 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. Grayson County's median household income of $72,182 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 Anderson County and Wood County.