| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 7,415 | 18,503 | 26,536 | |
| 2020 | R | 8,911 | 19,141 | 28,731 | |
| 2016 | R | 6,809 | 15,494 | 23,908 | |
| 2012 | R | 7,934 | 14,235 | 22,977 | |
| 2008 | R | 8,945 | 14,843 | 24,560 | |
| 2004 | R | 7,504 | 15,572 | 23,444 | |
| 2000 | R | 6,507 | 13,270 | 20,854 | |
| 1996 | R | 7,290 | 10,292 | 20,443 | |
| 1992 | D | 7,508 | 7,419 | 20,979 | |
| 1988 | R | 7,213 | 9,854 | 17,434 | |
| 1984 | R | 6,527 | 11,586 | 18,455 | |
| 1980 | R | 4,832 | 9,140 | 15,457 | |
| 1976 | D | 6,990 | 6,110 | 13,635 | |
| 1972 | R | 5,175 | 6,054 | 12,424 | |
| 1968 | R | 4,565 | 5,198 | 10,999 | |
| 1964 | D | 6,928 | 4,529 | 11,467 | |
| 1960 | R | 5,483 | 5,522 | 11,052 | |
| 1956 | R | 4,143 | 4,866 | 9,042 | |
| 1952 | R | 2,953 | 5,436 | 8,465 | |
| 1948 | R | 2,920 | 3,348 | 6,530 | |
| 1944 | D | 3,130 | 2,903 | 6,074 | |
| 1940 | D | 3,618 | 2,913 | 6,628 | |
| 1936 | D | 3,687 | 2,376 | 6,178 | |
| 1932 | D | 3,534 | 2,001 | 5,851 | |
| 1928 | R | 1,650 | 3,393 | 5,174 | |
| 1924 | R | 486 | 1,943 | 4,227 | |
| 1920 | R | 1,079 | 2,462 | 3,983 | |
| 1916 | D | 2,534 | 1,739 | 4,788 | |
| 1912 | D | 1,595 | 0 | 3,382 | |
| 1908 | R | 894 | 1,064 | 2,242 | |
| 1904 | R | 720 | 1,234 | 2,191 | |
| 1900 | R | 1,138 | 1,210 | 2,403 | |
| 1896 | D | 1,135 | 969 | 2,135 | |
| 1892 | D | 1,045 | 969 | 2,233 | |
| 1888 | D | 1,290 | 1,181 | 2,508 | |
| 1884 | D | 1,146 | 1,075 | 2,249 | |
| 1880 | D | 954 | 868 | 1,823 | |
| 1876 | D | 674 | 646 | 1,320 |
Tehama's ranching and timber economy anchors a political profile that sits well outside California's statewide norm — the 2024 presidential margin of R+42 placed it among the state's handful of deeply red rural counties.
The Democratic margin in Tehama County peaked at forty-seven points in 1912. By 1996 the county had flipped, voting Republican for the first time in many years. The 2024 margin was forty-two points, the most Republican-leaning result in the county's modern history.
The economic context is the key. Tehama County's median household income of $63,784 sits well below state and national norms, and 16% 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 Lassen County and Laramie County.