| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 22,034 | 23,768 | 47,593 | |
| 2020 | R | 22,917 | 23,732 | 48,291 | |
| 2016 | R | 16,420 | 18,940 | 40,295 | |
| 2012 | R | 16,292 | 17,819 | 35,257 | |
| 2008 | R | 17,536 | 17,714 | 36,207 | |
| 2004 | R | 15,484 | 19,508 | 35,489 | |
| 2000 | R | 11,921 | 14,988 | 28,449 | |
| 1996 | R | 10,942 | 11,478 | 25,331 | |
| 1992 | R | 9,551 | 10,082 | 25,614 | |
| 1988 | R | 9,626 | 10,553 | 20,621 | |
| 1984 | R | 8,709 | 12,678 | 21,432 | |
| 1980 | R | 7,833 | 10,006 | 20,531 | |
| 1976 | R | 8,141 | 8,528 | 17,530 | |
| 1972 | R | 5,908 | 8,985 | 15,609 | |
| 1968 | R | 4,961 | 6,997 | 12,571 | |
| 1964 | D | 7,292 | 4,319 | 11,629 | |
| 1960 | R | 4,578 | 6,709 | 11,298 | |
| 1956 | R | 4,047 | 6,404 | 10,451 | |
| 1952 | R | 2,983 | 6,850 | 9,869 | |
| 1948 | R | 3,451 | 4,328 | 8,012 | |
| 1944 | R | 3,318 | 3,904 | 7,340 | |
| 1940 | R | 4,077 | 4,211 | 8,348 | |
| 1936 | D | 3,694 | 2,246 | 6,498 | |
| 1932 | D | 3,705 | 2,548 | 6,514 | |
| 1928 | R | 1,724 | 3,244 | 5,034 | |
| 1924 | R | 1,621 | 2,755 | 5,223 | |
| 1920 | R | 1,653 | 2,709 | 4,594 | |
| 1916 | R | 2,844 | 2,899 | 6,054 | |
| 1912 | D | 1,201 | 1,043 | 3,252 | |
| 1908 | R | 1,113 | 1,456 | 2,807 | |
| 1904 | R | 521 | 1,380 | 2,168 | |
| 1900 | R | 991 | 1,163 | 2,298 | |
| 1896 | D | 1,334 | 1,253 | 2,647 | |
| 1892 | R | 432 | 943 | 2,203 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Polk County sits west of Salem along the Willamette River, blending rural farmland with small cities like Dallas and Independence. It shifted modestly rightward in 2024 but has remained competitive across recent cycles.
The Democratic margin in Polk County has rarely exceeded twenty-six points in modern history; the Republican margin has rarely exceeded forty points. 2024 delivered the county to the Republican candidate by four points.
Polk County's demographics resemble the country more than they resemble most counties. A 78% non-Hispanic-white share, a 13% poverty rate, and a median household income of $85,118 — all within the broad national range. The county's voting pattern over the last decade is most similar to that of Yamhill County and Jackson County.
