| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 3,600 | 9,353 | 13,032 | |
| 2020 | R | 3,823 | 8,890 | 12,939 | |
| 2016 | R | 3,146 | 7,400 | 11,325 | |
| 2012 | R | 4,724 | 5,651 | 10,522 | |
| 2008 | R | 4,986 | 5,969 | 11,138 | |
| 2004 | R | 4,546 | 6,624 | 11,397 | |
| 2000 | R | 4,333 | 6,103 | 10,932 | |
| 1996 | D | 4,402 | 3,965 | 10,185 | |
| 1992 | R | 3,676 | 4,101 | 11,032 | |
| 1988 | R | 4,252 | 5,787 | 10,138 | |
| 1984 | R | 2,757 | 7,069 | 9,860 | |
| 1980 | R | 3,973 | 4,937 | 9,822 | |
| 1976 | R | 3,764 | 5,840 | 9,633 | |
| 1972 | R | 2,987 | 6,591 | 9,608 | |
| 1968 | R | 3,205 | 5,524 | 9,180 | |
| 1964 | D | 6,584 | 3,185 | 9,779 | |
| 1960 | R | 4,056 | 6,632 | 10,697 | |
| 1956 | R | 2,536 | 7,764 | 10,300 | |
| 1952 | R | 2,927 | 7,622 | 10,576 | |
| 1948 | R | 3,211 | 5,692 | 9,078 | |
| 1944 | R | 3,441 | 6,256 | 9,715 | |
| 1940 | R | 3,466 | 8,049 | 11,532 | |
| 1936 | R | 3,263 | 8,048 | 11,426 | |
| 1932 | R | 4,086 | 6,258 | 10,424 | |
| 1928 | R | 4,161 | 7,175 | 11,344 | |
| 1924 | R | 2,801 | 6,066 | 9,057 | |
| 1920 | R | 2,673 | 5,906 | 8,692 | |
| 1916 | R | 2,675 | 3,418 | 6,226 | |
| 1912 | D | 2,339 | 2,064 | 6,093 | |
| 1908 | R | 2,810 | 4,159 | 7,155 | |
| 1904 | R | 2,842 | 4,242 | 7,248 | |
| 1900 | R | 2,857 | 4,308 | 7,262 | |
| 1896 | R | 3,042 | 4,461 | 7,647 | |
| 1892 | R | 3,369 | 3,965 | 7,661 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Tucked against the Tug Hill Plateau, Lewis County delivered a 44-point Republican presidential margin in 2024, making it among the state's sharpest rural-urban contrasts in a cycle where New York's statewide result ran in the opposite direction.
The Democratic margin in Lewis County peaked at thirty-five points in 1964. By 2000 the county had flipped, voting Republican for the first time in many years. The 2024 margin was forty-four points, the most Republican-leaning result in the county's modern history.
The economic context is the key. Lewis County's median household income of $68,182 sits well below state and national norms, and 12% 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 Butler County and Bath County.