| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 857 | 3,476 | 4,378 | |
| 2020 | R | 936 | 3,477 | 4,483 | |
| 2016 | R | 853 | 3,159 | 4,156 | |
| 2012 | R | 1,398 | 2,564 | 4,057 | |
| 2008 | R | 1,703 | 2,533 | 4,314 | |
| 2004 | R | 1,647 | 2,632 | 4,307 | |
| 2000 | R | 1,860 | 2,175 | 4,094 | |
| 1996 | D | 1,938 | 1,333 | 3,831 | |
| 1992 | D | 2,060 | 1,153 | 4,187 | |
| 1988 | D | 2,461 | 1,542 | 4,014 | |
| 1984 | R | 1,992 | 2,163 | 4,155 | |
| 1980 | D | 2,445 | 2,026 | 4,555 | |
| 1976 | D | 3,039 | 1,585 | 4,650 | |
| 1972 | D | 2,299 | 2,141 | 4,440 | |
| 1968 | D | 2,776 | 1,349 | 4,641 | |
| 1964 | D | 4,103 | 928 | 5,031 | |
| 1960 | D | 4,011 | 1,519 | 5,530 | |
| 1956 | D | 4,412 | 1,331 | 5,743 | |
| 1952 | D | 4,760 | 1,488 | 6,259 | |
| 1948 | D | 4,769 | 809 | 5,585 | |
| 1944 | D | 5,000 | 1,098 | 6,106 | |
| 1940 | D | 6,018 | 1,200 | 7,231 | |
| 1936 | D | 6,376 | 939 | 7,340 | |
| 1932 | D | 6,210 | 1,714 | 7,968 | |
| 1928 | D | 4,957 | 1,378 | 6,354 | |
| 1924 | D | 5,597 | 1,141 | 6,910 | |
| 1920 | D | 6,136 | 1,406 | 7,635 | |
| 1916 | D | 3,738 | 742 | 4,581 | |
| 1912 | D | 3,586 | 583 | 4,470 | |
| 1908 | D | 3,772 | 871 | 4,681 | |
| 1904 | D | 3,487 | 790 | 4,349 | |
| 1900 | D | 4,016 | 795 | 4,877 | |
| 1896 | D | 4,379 | 892 | 5,294 | |
| 1892 | D | 3,863 | 787 | 4,750 | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Monroe County's R+59.8 margin in 2024 places it among Missouri's most one-sided presidential contests, reflecting a broader realignment of sparsely populated agricultural counties that once anchored statewide Democratic coalitions.
The unraveling was not abrupt. The Democratic margin in Monroe County peaked at seventy-four points in 1936; it narrowed steadily over the late twentieth century. The 2000 election delivered the county to the Republican party for the first time in many years, by a margin of eight points. By 2024, the margin had widened further.
The economic and demographic context is severe. Monroe County's median household income of $54,516 is among the lowest of any county in the United States; 14% of residents live below the federal poverty line. The county's voting pattern over the last decade is most similar to that of Ralls County and Lewis County.