| Election Name: | 2004 Wyoming Senate election |
| Country: | Wyoming |
| Type: | legislative |
| Previous Election: | 2002 Wyoming Senate election |
| Previous Year: | 2002 |
| Next Election: | 2006 Wyoming Senate election |
| Next Year: | 2006 |
| Seats For Election: | 16 of 30 seats in the Wyoming Senate Even-numbered seats up, unexpired term in District 1 |
| Leader1: | April Brimmer-Kunz (retiring) |
| Party1: | Republican Party (United States) |
| Leaders Seat1: | 4th district |
| Seats Before1: | 20 |
| Seats After1: | 23 |
| Seat Change1: | 3 |
| Popular Vote1: | 86,459 |
| Percentage1: | 74.17% |
| Leader2: | E. Jayne Mockler |
| Party2: | Democratic Party (United States) |
| Leaders Seat2: | 8th district |
| Seats Before2: | 10 |
| Seats After2: | 7 |
| Seat Change2: | 3 |
| Popular Vote2: | 30,103 |
| Percentage2: | 25.83% |
| Map Size: | 350px |
| Senate President | |
| Before Election: | April Brimmer-Kunz |
| Before Party: | Republican Party (United States) |
| After Election: | Grant Larson |
| After Party: | Republican Party (United States) |
The 2004 Wyoming Senate election was held on November 2, 2004, to elect members to the Wyoming Senate for its 58th session as part of the 2004 United States elections. Partisan primaries were held on August 17. All even-numbered seats were up for election as well as an unexpired term for District 1. Republicans picked up three seats in the legislative chamber.
| Party | Candidates | Votes | % | Seats | |||||
|---|---|---|---|---|---|---|---|---|---|
| Before | Up | Won | After | +/– | |||||
| Republican | 14 | 86,459 | 74.17 | 20 | 11 | 14 | 23 | 3 | |
| Democratic | 9 | 30,103 | 25.83 | 10 | 5 | 2 | 7 | 3 | |
| Total | 116,562 | 100% | 30 | 16 | 30 | ||||
†: Incumbent did not run for reelection.††: Incumbent defeated in primary.†††: Incumbent defeated in general election.‡: Unexpired term.
| District | Incumbent | Party | Elected Senator | Party | ||
|---|---|---|---|---|---|---|
| 1st ‡ | Chuck Townsend | Rep | Chuck Townsend | Rep | ||
| 2nd | Jim Anderson | Rep | Jim Anderson | Rep | ||
| 4th | April Brimmer-Kunz † | Rep | Tony Ross | Rep | ||
| 6th | Rich Cathcart † | Dem | Wayne Johnson | Rep | ||
| 8th | E. Jayne Mockler | Dem | E. Jayne Mockler | Dem | ||
| 10th | Irene Devin † | Rep | Phil Nicholas | Rep | ||
| 12th | Rae Lynn Job | Dem | Rae Lynn Job | Dem | ||
| 14th | Larry Caller ††† | Dem | Stan Cooper | Rep | ||
| 16th | Delaine Roberts † | Rep | Pat Aullman | Rep | ||
| 18th | Hank Coe | Rep | Hank Coe | Rep | ||
| 20th | Gerald Geis | Rep | Gerald Geis | Rep | ||
| 22nd | John Schiffer | Rep | John Schiffer | Rep | ||
| 24th | Dick Erb †† | Rep | Michael Von Flatern | Rep | ||
| 26th | Robert A. Peck | Rep | Robert A. Peck | Rep | ||
| 28th | Keith Goodenough ††† | Dem | Kit Jennings | Rep | ||
| 30th | Charles K. Scott | Rep | Charles K. Scott | Rep | ||