| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | D | 6,407 | 5,252 | 11,894 | |
| 2020 | D | 6,610 | 5,221 | 12,106 | |
| 2016 | D | 5,164 | 4,790 | 10,665 | |
| 2012 | D | 5,094 | 4,946 | 10,296 | |
| 2008 | D | 5,268 | 4,725 | 10,126 | |
| 2004 | R | 3,967 | 5,283 | 9,343 | |
| 2000 | R | 3,318 | 4,314 | 7,886 | |
| 1996 | R | 3,027 | 3,681 | 7,222 | |
| 1992 | R | 2,768 | 3,833 | 7,701 | |
| 1988 | R | 2,300 | 4,497 | 6,862 | |
| 1984 | R | 2,064 | 5,055 | 7,152 | |
| 1980 | R | 2,006 | 4,240 | 6,623 | |
| 1976 | R | 2,346 | 4,075 | 6,484 | |
| 1972 | R | 1,418 | 4,647 | 6,151 | |
| 1968 | R | 1,360 | 2,695 | 4,833 | |
| 1964 | D | 2,254 | 2,180 | 4,437 | |
| 1960 | R | 1,203 | 2,326 | 3,545 | |
| 1956 | R | 945 | 2,375 | 3,419 | |
| 1952 | R | 1,055 | 2,375 | 3,432 | |
| 1948 | R | 894 | 1,272 | 2,546 | |
| 1944 | R | 1,000 | 1,095 | 2,102 | |
| 1940 | D | 1,114 | 945 | 2,067 | |
| 1936 | D | 1,096 | 743 | 1,851 | |
| 1932 | D | 1,179 | 698 | 1,910 | |
| 1928 | R | 794 | 1,168 | 1,962 | |
| 1924 | D | 820 | 420 | 1,258 | |
| 1920 | D | 736 | 540 | 1,300 | |
| 1916 | D | 468 | 196 | 684 | |
| 1912 | D | 447 | 141 | 677 | |
| 1908 | D | 449 | 266 | 744 | |
| 1904 | D | 394 | 146 | 553 | |
| 1900 | D | 593 | 423 | 1,027 | |
| 1896 | D | 490 | 447 | 986 | |
| 1892 | D | 579 | 468 | 1,072 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Winchester, one of Virginia's oldest independent cities, has shifted noticeably leftward over the past decade, posting a D+9.8 margin in 2024 — a significant departure from its historically Republican-leaning Shenandoah Valley surroundings.
The county's recent history is a story of close margins. The Democratic margin reached forty-five points in 1912; the Republican margin reached fifty-two points in 1972. Most other elections have been decided by single-digit points.
Winchester city's demographics — a population of 27,913, a 62% non-Hispanic-white share, a median household income of $63,974 — situate the county close to national averages on several dimensions. The county's voting pattern over the last decade is most similar to that of Staunton city and DuPage County.
