| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 2,782 | 4,744 | 7,650 | |
| 2020 | R | 3,172 | 4,732 | 8,032 | |
| 2016 | R | 3,179 | 4,375 | 8,159 | |
| 2012 | D | 4,680 | 3,472 | 8,257 | |
| 2008 | D | 4,822 | 3,051 | 8,091 | |
| 2004 | D | 4,349 | 3,745 | 8,167 | |
| 2000 | D | 3,830 | 3,191 | 7,238 | |
| 1996 | D | 3,769 | 2,379 | 6,887 | |
| 1992 | D | 3,688 | 2,404 | 7,750 | |
| 1988 | D | 4,377 | 3,266 | 7,733 | |
| 1984 | R | 4,154 | 4,341 | 8,553 | |
| 1980 | R | 3,634 | 4,665 | 9,118 | |
| 1976 | D | 4,646 | 4,361 | 9,178 | |
| 1972 | R | 3,338 | 4,726 | 8,192 | |
| 1968 | R | 2,971 | 4,792 | 8,178 | |
| 1964 | D | 5,317 | 3,721 | 9,043 | |
| 1960 | R | 3,970 | 5,774 | 9,746 | |
| 1956 | R | 3,739 | 6,172 | 9,927 | |
| 1952 | R | 2,999 | 7,042 | 10,054 | |
| 1948 | R | 3,688 | 4,644 | 8,497 | |
| 1944 | R | 3,446 | 5,248 | 8,731 | |
| 1940 | R | 4,167 | 5,829 | 10,031 | |
| 1936 | R | 4,242 | 4,267 | 9,031 | |
| 1932 | D | 4,563 | 4,083 | 8,781 | |
| 1928 | R | 2,074 | 5,675 | 7,795 | |
| 1924 | R | 529 | 5,012 | 7,594 | |
| 1920 | R | 933 | 6,106 | 7,197 | |
| 1916 | R | 1,250 | 2,691 | 4,071 | |
| 1912 | D | 1,244 | 1,216 | 3,906 | |
| 1908 | R | 1,250 | 2,462 | 3,780 | |
| 1904 | R | 761 | 2,820 | 3,697 | |
| 1900 | R | 1,295 | 2,843 | 4,208 | |
| 1896 | R | 1,461 | 2,749 | 4,285 | |
| 1892 | R | 1,387 | 2,017 | 3,578 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Floyd County's 16,900 residents are concentrated in Charles City along the Cedar River, and its presidential margins have shifted roughly 30 points toward Republicans over the past two decades as rural Iowa realigned.
The Democratic margin in Floyd County has rarely exceeded twenty-two points in modern history; the Republican margin has rarely exceeded seventy-two points. 2024 delivered the county to the Republican candidate by twenty-six points.
Floyd County's demographics resemble the country more than they resemble most counties. A 90% non-Hispanic-white share, a 12% poverty rate, and a median household income of $68,557 — all within the broad national range. The county's voting pattern over the last decade is most similar to that of Jackson County and Buchanan County.