How many U.S. Senate seats changed party in 2004?

9 seats changed party in the 2004 Senate elections: Colorado (Republican to Democrat), Florida (Democrat to Republican), Georgia (Democrat to Republican), Illinois (Republican to Democrat), Indiana (Republican to Democrat), Louisiana (Democrat to Republican), North Carolina (Democrat to Republican), South Carolina (Democrat to Republican), South Dakota (Democrat to Republican).

Which new senators were elected in 2004?

10 new senators won seats in 2004: Kenneth Salazar (Democrat-CO), Mel Martinez (Republican-FL), Johnny Isakson (Republican-GA), Barack Obama (Democrat-IL), Evan Bayh (Democrat-IN), David Vitter (Republican-LA), Richard Burr (Republican-NC), Thomas Coburn (Republican-OK), James DeMint (Republican-SC), John Thune (Republican-SD).

2004 U.S. Senate Elections: Results

34 Senate seats were decided on Tuesday, November 2, 2004: the 34 Class III seats. 24 incumbents kept their seats, 10 new senators were elected, and 9 seats changed party.

All cycles 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 2022 2024 2026 2028 2030

Seats on the ballot

34 Class III

Held going in

18 Democrat · 16 Republican

New senators

24 incumbents re-elected

Seats that changed party

CO, FL, GA, IL, IN, LA, NC, SC, SD

Every Seat on the 2004 Ballot

Incumbent is whoever held the seat on election day; the result is who was sworn in for it afterwards.

State ▲	Incumbent ↕	Party ↕	Seat ↕	Since ↕	Age on Election Day ↕	Result ↕
Alabama	Richard Shelby Since 1987	Republican	Class III	1987		Re-elected
Alaska	Lisa Murkowski Since 2002 · age 47	Republican	Class III Appointed	2002	47	Re-elected
Arizona	John McCain, III Since 1987	Republican	Class III	1987		Re-elected
Arkansas	Blanche Lincoln Since 1999	Democrat	Class III	1999		Re-elected
California	Barbara Boxer Since 1993	Democrat	Class III	1993		Re-elected
Colorado	Ben Campbell Since 1993	Republican	Class III	1993		Kenneth Salazar (Democrat) Party change
Connecticut	Christopher Dodd Since 1981	Democrat	Class III	1981		Re-elected
Florida	Bob Graham Since 1987	Democrat	Class III	1987		Mel Martinez (Republican) Party change
Georgia	Zell Miller Since 2000	Democrat	Class III Appointed	2000		Johnny Isakson (Republican) Party change
Hawaii	Daniel Inouye Since 1963	Democrat	Class III	1963		Re-elected
Idaho	Mike Crapo Since 1999 · age 53	Republican	Class III	1999	53	Re-elected
Illinois	Peter Fitzgerald Since 1999	Republican	Class III	1999		Barack Obama (Democrat) Party change
Indiana	Daniel Coats Since 1989	Republican	Class III	1989		Evan Bayh (Democrat) Party change
Iowa	Chuck Grassley Since 1981 · age 71	Republican	Class III	1981	71	Re-elected
Kansas	Sam Brownback Since 1996	Republican	Class III	1996		Re-elected
Kentucky	James Bunning Since 1999	Republican	Class III	1999		Re-elected
Louisiana	John Breaux Since 1987	Democrat	Class III	1987		David Vitter (Republican) Party change
Maryland	Barbara Mikulski Since 1987	Democrat	Class III	1987		Re-elected
Missouri	Kit Bond Since 1987	Republican	Class III	1987		Re-elected
Nevada	Harry Reid Since 1987	Democrat	Class III	1987		Re-elected
New Hampshire	Judd Gregg Since 1993	Republican	Class III	1993		Re-elected
New York	Chuck Schumer Since 1999 · age 53	Democrat	Class III	1999	53	Re-elected
North Carolina	John Edwards Since 1999	Democrat	Class III	1999		Richard Burr (Republican) Party change
North Dakota	Byron Dorgan Since 1992	Democrat	Class III	1992		Re-elected
Ohio	George Voinovich Since 1999	Republican	Class III	1999		Re-elected
Oklahoma	Donald Nickles Since 1981	Republican	Class III	1981		Thomas Coburn (Republican)
Oregon	Ron Wyden Since 1996 · age 55	Democrat	Class III	1996	55	Re-elected
Pennsylvania	Arlen Specter Since 1981	Republican	Class III	1981		Re-elected
South Carolina	Fritz Hollings Since 1966	Democrat	Class III	1966		James DeMint (Republican) Party change
South Dakota	Thomas Daschle Since 1987	Democrat	Class III	1987		John Thune (Republican) Party change
Utah	Bob Bennett Since 1993	Republican	Class III	1993		Re-elected
Vermont	Patrick Leahy Since 1975	Democrat	Class III	1975		Re-elected
Washington	Patty Murray Since 1993 · age 54	Democrat	Class III	1993	54	Re-elected
Wisconsin	Russell Feingold Since 1993	Democrat	Class III	1993		Re-elected

New Senators Elected in 2004

Kenneth Salazar

Democrat · Colorado

Succeeded Ben Campbell (Republican)

Mel Martinez

Republican · Florida

Succeeded Bob Graham (Democrat)

Johnny Isakson

Republican · Georgia

Succeeded Zell Miller (Democrat)

Barack Obama

Democrat · Illinois

Succeeded Peter Fitzgerald (Republican)

Evan Bayh

Democrat · Indiana

Succeeded Daniel Coats (Republican)

David Vitter

Republican · Louisiana

Succeeded John Breaux (Democrat)

Richard Burr

Republican · North Carolina

Succeeded John Edwards (Democrat)

Thomas Coburn

Republican · Oklahoma

Succeeded Donald Nickles

James DeMint

Republican · South Carolina

Succeeded Fritz Hollings (Democrat)

John Thune

Republican · South Dakota

Succeeded Thomas Daschle (Democrat)

About this page

Seats, incumbents and results are derived from the Senate's service records (via the congress-legislators dataset): the seats on a year's ballot are the class whose terms end the following January, plus any seat held by appointment pending a special election, and a result is recorded when the winner is sworn in. Incumbent status and candidates for the next election come from FEC candidate filings; a seat is listed as open when the FEC tags its candidates as running for a seat with no incumbent. Election day is the Tuesday after the first Monday in November. See every cycle since 1990, the seniority list and the voting analysis.