| Election Name: | 2004 Delaware Senate election |
| Country: | Delaware |
| Type: | legislative |
| Ongoing: | no |
| Previous Election: | 2002 Delaware Senate election |
| Previous Year: | 2002 |
| Next Election: | 2006 Delaware Senate election |
| Next Year: | 2006 |
| Seats For Election: | 10 of the 21 seats in the Delaware Senate |
| Majority Seats: | 11 |
| Image1: | 3x4.svg |
| Leader1: | Thurman Adams Jr. |
| Party1: | Democratic |
| Colour1: | 3333ff |
| Leader Since1: | January 2003 |
| Leaders Seat1: | 19th - Bridgeville |
| Last Election1: | 13 |
| Seats Before1: | 13 |
| Seats1: | 4 |
| Seats After1: | 13 |
| Popular Vote1: | 71,101 |
| Percentage1: | 47.74% |
| Leader2: | John Still III |
| Party2: | Republican |
| Colour2: | ff3333 |
| Leader Since2: | January 2003 |
| Leaders Seat2: | 17th - Dover |
| Last Election2: | 8 |
| Seats Before2: | 8 |
| Seats2: | 6 |
| Seats After2: | 8 |
| Popular Vote2: | 77,609 |
| Percentage2: | 52.11% |
| Map Size: | 130px |
| President pro tempore | |
| Before Election: | Thurman Adams Jr. |
| Before Party: | Democratic |
| After Election: | Thurman Adams Jr. |
| After Party: | Democratic |
The 2004 Delaware Senate election was held on November 2, 2004, to elect 10 of the 21 members to Delaware's Senate. The election coincided with elections for other offices, including for U.S. President, U.S. House of Representatives, Governor, Lieutenant Governor, and state house. The primary election was held on September 11, 2004.[1]
| District | Incumbent | Party | Elected Senator | Party | |||
|---|---|---|---|---|---|---|---|
| 2 | Margaret Rose Henry | Dem | Margaret Rose Henry | Dem | |||
| 3 | Robert Marshall | Dem | Robert Marshall | Dem | |||
| 4 | Charlie Copeland | Rep | Charlie Copeland | Rep | |||
| 6 | Liane Sorenson | Rep | Liane Sorenson | Rep | |||
| 10 | Rep | Rep | |||||
| 11 | Tony DeLuca | Dem | Tony DeLuca | Dem | |||
| 16 | Colin Bonini | Rep | Colin Bonini | Rep | |||
| 17 | John Still III | Rep | John Still III | Rep | |||
| 18 | Gary Simpson | Rep | Gary Simpson | Rep | |||
| 21 | Robert Venables Sr. | Dem | Robert Venables Sr. | Dem | |||
| Party | Candi- dates | Votes | Seats | |||||
|---|---|---|---|---|---|---|---|---|
| No. | % | No. | +/– ! | % | ||||
| Democratic | 8 | 71,101 | 47.74% | 16 | 61.90% | |||
| 7 | 77,609 | 52.11% | 5 | 38.10% | ||||
| 1 | 214 | 0.14% | 0 | 0.00% | ||||
| Total | 16 | 148,924 | 100% | 21 | 100% | |||
Incumbent Democrat Majority Leader Margaret Rose Henry has represented the 2nd district since 1994.
Incumbent Democrat Robert Marshall has represented the 3rd district since 1979.
Incumbent Republican Charlie Copeland has represented the 4th district since 2003.
Incumbent Republican Liane Sorenson has represented the 6th district since 1995.
Incumbent Republican Steven Amick has represented the 10th district since 1995.
Incumbent Democrat Tony DeLuca has represented the 11th district since 1999.
Incumbent Republican Colin Bonini has represented the 16th district since 1995.
Incumbent Republican Minority Leader John Still III has represented the 17th district since 1988.
Incumbent Republican Gary Simpson has represented the 18th district since 1999.
Incumbent Democrat Robert Venables Sr. has represented the 21st district since 1989.