| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 5,379 | 13,658 | 19,385 | |
| 2020 | R | 5,637 | 13,480 | 19,601 | |
| 2016 | R | 4,766 | 12,709 | 18,713 | |
| 2012 | R | 5,798 | 11,895 | 18,286 | |
| 2008 | R | 7,394 | 11,706 | 19,438 | |
| 2004 | R | 6,666 | 11,874 | 18,700 | |
| 2000 | R | 6,262 | 9,444 | 16,146 | |
| 1996 | R | 6,405 | 6,990 | 15,297 | |
| 1992 | D | 6,852 | 6,040 | 16,739 | |
| 1988 | R | 5,867 | 8,329 | 14,253 | |
| 1984 | R | 5,074 | 9,012 | 14,086 | |
| 1980 | R | 5,470 | 7,366 | 13,566 | |
| 1976 | D | 6,261 | 6,153 | 12,512 | |
| 1972 | R | 3,567 | 7,598 | 11,165 | |
| 1968 | R | 4,211 | 5,577 | 11,783 | |
| 1964 | D | 5,776 | 3,755 | 9,531 | |
| 1960 | R | 4,576 | 5,663 | 10,239 | |
| 1956 | R | 4,761 | 4,773 | 9,534 | |
| 1952 | D | 4,846 | 4,694 | 9,554 | |
| 1948 | D | 5,202 | 3,053 | 8,277 | |
| 1944 | D | 4,256 | 3,180 | 7,449 | |
| 1940 | D | 4,780 | 3,319 | 8,114 | |
| 1936 | D | 4,658 | 2,690 | 7,381 | |
| 1932 | D | 4,858 | 1,794 | 6,720 | |
| 1928 | R | 2,896 | 2,967 | 5,874 | |
| 1924 | D | 2,918 | 2,085 | 5,500 | |
| 1920 | R | 2,422 | 2,692 | 5,152 | |
| 1916 | D | 1,887 | 1,487 | 3,423 | |
| 1912 | D | 1,565 | 782 | 2,816 | |
| 1908 | D | 1,804 | 1,520 | 3,378 | |
| 1904 | D | 1,384 | 1,371 | 2,889 | |
| 1900 | D | 1,603 | 1,153 | 2,837 | |
| 1896 | D | 1,816 | 1,038 | 2,868 | |
| 1892 | D | 1,287 | 883 | 2,386 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Phelps County anchors the Missouri Ozarks, where Missouri S&T's engineering campus in Rolla adds a modest college-town layer to an otherwise rural electorate that swung Republican by nearly 43 points in 2024.
The Democratic margin in Phelps County peaked at forty-six points in 1932. By 1996 the county had flipped, voting Republican for the first time in many years. The 2024 margin was forty-three points, the most Republican-leaning result in the county's modern history.
The economic context is the key. Phelps County's median household income of $58,396 sits well below state and national norms, and 17% of residents live below the federal poverty line. The shift here is part of a broader realignment of working-class places across the country. The county's voting pattern over the last decade is most similar to that of Johnson County and Douglas County.