| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 14,549 | 20,386 | 35,062 | |
| 2020 | R | 15,489 | 18,665 | 34,647 | |
| 2016 | R | 12,568 | 15,931 | 29,955 | |
| 2012 | D | 15,268 | 12,705 | 28,415 | |
| 2008 | D | 16,850 | 13,900 | 31,183 | |
| 2004 | R | 15,034 | 15,319 | 30,966 | |
| 2000 | D | 14,348 | 12,703 | 28,528 | |
| 1996 | D | 15,052 | 9,321 | 28,244 | |
| 1992 | D | 13,717 | 11,396 | 31,635 | |
| 1988 | R | 11,635 | 15,713 | 27,568 | |
| 1984 | R | 10,475 | 18,037 | 28,590 | |
| 1980 | R | 9,553 | 15,089 | 27,218 | |
| 1976 | D | 14,189 | 13,709 | 28,096 | |
| 1972 | R | 9,847 | 17,035 | 26,938 | |
| 1968 | R | 10,860 | 11,657 | 24,198 | |
| 1964 | D | 16,728 | 8,006 | 24,775 | |
| 1960 | R | 11,486 | 13,744 | 25,279 | |
| 1956 | R | 8,937 | 15,845 | 24,782 | |
| 1952 | R | 8,421 | 14,926 | 23,626 | |
| 1948 | R | 7,654 | 11,253 | 21,152 | |
| 1944 | R | 8,836 | 11,258 | 20,167 | |
| 1940 | R | 9,785 | 11,877 | 21,738 | |
| 1936 | D | 9,908 | 9,757 | 19,982 | |
| 1932 | D | 9,656 | 8,294 | 18,517 | |
| 1928 | R | 6,207 | 10,331 | 16,861 | |
| 1924 | R | 4,057 | 7,734 | 13,604 | |
| 1920 | R | 3,623 | 8,029 | 12,458 | |
| 1916 | R | 3,659 | 4,340 | 8,181 | |
| 1912 | D | 3,864 | 3,039 | 8,092 | |
| 1908 | R | 3,911 | 4,593 | 8,746 | |
| 1904 | R | 3,582 | 4,452 | 8,189 | |
| 1900 | R | 3,625 | 4,393 | 8,148 | |
| 1896 | R | 3,073 | 4,589 | 7,864 | |
| 1892 | R | 3,567 | 3,664 | 7,589 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Once a Democratic stronghold anchored by Borscht Belt tourism and labor voters, Sullivan County now votes Republican by double digits, reflecting a rural realignment visible across the broader Catskills region.
The Democratic margin in Sullivan County has rarely exceeded thirty-five points in modern history; the Republican margin has rarely exceeded thirty-five points. 2024 delivered the county to the Republican candidate by seventeen points.
Sullivan County's demographics resemble the country more than they resemble most counties. A 70% non-Hispanic-white share, a 16% poverty rate, and a median household income of $72,382 — all within the broad national range. The county's voting pattern over the last decade is most similar to that of Westmoreland County and Cayuga County.
