| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 3,979 | 10,100 | 14,349 | |
| 2020 | R | 4,357 | 9,668 | 14,313 | |
| 2016 | R | 4,385 | 8,944 | 13,949 | |
| 2012 | R | 5,432 | 7,731 | 13,163 | |
| 2008 | R | 6,191 | 8,727 | 14,918 | |
| 2004 | R | 7,367 | 8,363 | 15,730 | |
| 2000 | D | 7,186 | 5,797 | 13,178 | |
| 1996 | D | 7,555 | 4,246 | 13,337 | |
| 1992 | D | 7,767 | 4,586 | 15,421 | |
| 1988 | D | 8,262 | 5,674 | 14,004 | |
| 1984 | R | 7,380 | 8,704 | 16,189 | |
| 1980 | D | 7,236 | 6,652 | 14,285 | |
| 1976 | D | 8,499 | 5,333 | 13,963 | |
| 1972 | R | 4,494 | 8,706 | 13,642 | |
| 1968 | D | 6,089 | 4,709 | 13,526 | |
| 1964 | D | 10,195 | 4,704 | 14,899 | |
| 1960 | D | 7,262 | 7,107 | 14,369 | |
| 1956 | D | 7,626 | 6,703 | 14,329 | |
| 1952 | D | 10,115 | 6,717 | 16,832 | |
| 1948 | D | 10,467 | 4,368 | 14,835 | |
| 1944 | D | 9,737 | 5,430 | 15,192 | |
| 1940 | D | 11,016 | 6,696 | 17,796 | |
| 1936 | D | 12,061 | 4,975 | 17,093 | |
| 1932 | D | 11,287 | 4,762 | 16,049 | |
| 1928 | R | 5,834 | 9,149 | 15,056 | |
| 1924 | R | 5,927 | 6,015 | 12,838 | |
| 1920 | R | 4,495 | 5,367 | 10,455 | |
| 1916 | D | 2,406 | 1,860 | 5,039 | |
| 1912 | D | 1,243 | 1,140 | 2,947 | |
| 1908 | R | 1,103 | 1,400 | 2,800 | |
| 1904 | — | — | — | — | |
| 1900 | — | — | — | — | |
| 1896 | — | — | — | — | |
| 1892 | — | — | — | — | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Home to the Muscogee (Creek) Nation capital at Okmulgee city, the county carries one of Oklahoma's higher shares of Native American residents — yet still returns lopsided Republican presidential margins exceeding 40 points.
The unraveling was not abrupt. The Democratic margin in Okmulgee County peaked at forty-one points in 1936; 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 six points. By 2024, the margin had widened further.
The economic and demographic context is severe. Okmulgee County's median household income of $54,029 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 McIntosh County and Mississippi County.