| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 40,190 | 43,955 | 86,684 | |
| 2020 | D | 48,991 | 39,397 | 90,993 | |
| 2016 | D | 37,317 | 28,725 | 71,127 | |
| 2012 | D | 33,005 | 27,581 | 62,222 | |
| 2008 | D | 34,031 | 28,704 | 64,051 | |
| 2004 | R | 24,491 | 32,773 | 57,960 | |
| 2000 | R | 22,726 | 26,102 | 50,418 | |
| 1996 | D | 21,786 | 20,847 | 46,938 | |
| 1992 | D | 20,133 | 17,981 | 49,284 | |
| 1988 | R | 20,105 | 21,717 | 42,414 | |
| 1984 | R | 17,012 | 24,997 | 42,477 | |
| 1980 | R | 15,886 | 18,043 | 36,996 | |
| 1976 | D | 16,637 | 14,842 | 32,208 | |
| 1972 | R | 13,914 | 17,737 | 32,648 | |
| 1968 | D | 14,453 | 11,595 | 28,349 | |
| 1964 | D | 19,431 | 8,814 | 28,269 | |
| 1960 | D | 15,545 | 11,990 | 27,646 | |
| 1956 | D | 13,366 | 11,430 | 24,852 | |
| 1952 | R | 11,316 | 12,865 | 24,395 | |
| 1948 | D | 9,959 | 7,721 | 18,124 | |
| 1944 | D | 9,192 | 6,518 | 15,779 | |
| 1940 | D | 10,501 | 6,101 | 16,784 | |
| 1936 | D | 9,208 | 3,230 | 12,668 | |
| 1932 | D | 7,202 | 2,920 | 10,734 | |
| 1928 | R | 2,970 | 4,644 | 7,718 | |
| 1924 | R | 710 | 3,573 | 6,749 | |
| 1920 | R | 1,537 | 3,457 | 5,488 | |
| 1916 | D | 2,637 | 2,132 | 5,236 | |
| 1912 | D | 1,978 | 0 | 4,228 | |
| 1908 | R | 1,100 | 1,107 | 2,483 | |
| 1904 | R | 863 | 972 | 1,981 | |
| 1900 | D | 1,081 | 811 | 1,950 | |
| 1896 | D | 1,117 | 653 | 1,802 | |
| 1892 | D | 995 | 782 | 1,972 | |
| 1888 | D | 972 | 773 | 1,796 | |
| 1884 | D | 953 | 809 | 1,779 | |
| 1880 | D | 736 | 516 | 1,256 | |
| 1876 | D | 804 | 558 | 1,362 |
Merced shifted to the Republican column by 4.4 points in 2024, a notable move for a majority-Hispanic agricultural county in California's Central Valley where dairy farming and field crops define the local economy.
The county's recent history is a story of close margins. The Democratic margin reached forty-seven points in 1936; the Republican margin reached forty-two points in 1924. Most other elections have been decided by single-digit points.
Merced County's demographics — a population of 290,201, a 32% non-Hispanic-white share, a median household income of $65,510 — 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 San Joaquin County and Fresno County.
