2004 Delaware Senate election

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.

District 2
Incumbent Democrat Majority Leader Margaret Rose Henry has represented the 2nd district since 1994.

District 3
Incumbent Democrat Robert Marshall has represented the 3rd district since 1979.

District 4
Incumbent Republican Charlie Copeland has represented the 4th district since 2003.

District 6
Incumbent Republican Liane Sorenson has represented the 6th district since 1995.

District 10
Incumbent Republican Steven Amick has represented the 10th district since 1995.

District 11
Incumbent Democrat Tony DeLuca has represented the 11th district since 1999.

District 16
Incumbent Republican Colin Bonini has represented the 16th district since 1995.

District 17
Incumbent Republican Minority Leader John Still III has represented the 17th district since 1988.

District 18
Incumbent Republican Gary Simpson has represented the 18th district since 1999.

District 21
Incumbent Democrat Robert Venables Sr. has represented the 21st district since 1989.