Skip to content
Congress Countdown
Map
On this page

Live Data

Members of Congress Who Switched Parties

52 party switches by 47 members since 1945 — 22 from Democrat to Republican, 6 from Republican to Democrat, and 11 to independent. The most recent: Kevin Kiley (CA), Republican to Independent, March 9, 2026.

Source: unitedstates/congress-legislators, read October 4, 2026

Quick Answer

Switches since 1945
52, by 47 members
Democrat → Republican
22
Republican → Democrat
6
To independent
11
Senators
11 switches
Most recent
Kevin Kiley, Republican → Independent, March 9, 2026
Still serving
Kevin Kiley, Jefferson Van Drew

Senators who switched parties (11)

Most recently Joe Manchin III (WV) in 2024.

Joe Manchin III (WV)

Democrat → Independent · mid-term

2024

Kyrsten Sinema (AZ)

Democrat → Independent · mid-term

2022

Arlen Specter (PA)

Republican → Democrat · mid-term

2009

Joseph Lieberman (CT)

Democrat → Independent · between terms

2007

Jim Jeffords (VT)

Republican → Independent · mid-term

2001

Ben Campbell (CO)

Democrat → Republican · mid-term

1995

Richard Shelby (AL)

Democrat → Republican · mid-term

1994

Harry Byrd Jr. (VA)

Democrat → Independent · between terms

1971

Strom Thurmond (SC)

Democrat → Republican · mid-term

1964

Wayne Morse (OR)

Independent → Democrat · between terms

1957

Wayne Morse (OR)

Republican → Independent · between terms

1951

One switch changed control of the chamber. In the evenly divided Senate of 2001, Republicans held the majority through Vice President Cheney’s tie-breaking vote until Jim Jeffords became an independent caucusing with Democrats, effective June 6, 2001 — handing Democrats control. The Senate historian’s account is on the 107th Congress page.

House members who switched parties (41)

Most recently Kevin Kiley (CA) in 2026.

Kevin Kiley (CA)

Republican → Independent · mid-term

2026

Paul Mitchell (MI)

Republican → Independent · mid-term

2020

Justin Amash (MI)

Independent → Libertarian · mid-term

2020

Jefferson Van Drew (NJ)

Democrat → Republican · mid-term

2019

Justin Amash (MI)

Republican → Independent · mid-term

2019

Gregorio Sablan (MP)

Independent → Democrat · between terms

2017

Gregorio Sablan (MP)

Democrat → Independent · between terms

2015

Parker Griffith (AL)

Democrat → Republican · mid-term

2009

Gregorio Sablan (MP)

Independent → Democrat · mid-term

2009

Rodney Alexander (LA)

Democrat → Republican · mid-term

2004

Ralph Hall (TX)

Democrat → Republican · mid-term

2004

Virgil Goode Jr. (VA)

Independent → Republican · mid-term

2002

Matthew Martínez (CA)

Democrat → Republican · mid-term

2000

Virgil Goode Jr. (VA)

Democrat → Independent · mid-term

2000

Michael Forbes (NY)

Republican → Democrat · mid-term

1999

Jo Ann Emerson (MO)

Independent → Republican · mid-term

1997

Wes Watkins (OK)

Democrat → Republican · between terms

1997

James Hayes (LA)

Democrat → Republican · mid-term

1995

Mike Parker (MS)

Democrat → Republican · mid-term

1995

Billy Tauzin (LA)

Democrat → Republican · mid-term

1995

Gregory Laughlin (TX)

Democrat → Republican · mid-term

1995

Nathan Deal (GA)

Democrat → Republican · mid-term

1995

Tommy Robinson (AR)

Democrat → Republican · mid-term

1989

James Grant (FL)

Democrat → Republican · mid-term

1989

Andy Ireland (FL)

Democrat → Republican · between terms

1985

Robert Stump (AZ)

Democrat → Republican · between terms

1983

Phil Gramm (TX)

Democrat → Republican · between terms

1983

Thomas Foglietta (PA)

Independent → Democrat · between terms

1983

Eugene Atkinson (PA)

Democrat → Republican · between terms

1981

Peter Peyser (NY)

Republican → Democrat · between terms

1979

John Jarman (OK)

Democrat → Republican · mid-term

1975

John Moakley (MA)

Ind. Democrat → Democrat · between terms

1975

Donald Riegle Jr. (MI)

Republican → Democrat · between terms

1975

Ogden Reid (NY)

Republican → Democrat · mid-term

1972

Albert Watson (SC)

Democrat → Republican · between terms

1967

Thomas Alford (AR)

Ind. Democrat → Democrat · between terms

1961

James Oliver (ME)

Republican → Democrat · between terms

1959

Franklin Roosevelt Jr. (NY)

Liberal → Democrat · between terms

1951

Gardner Withrow (WI)

Progressive → Republican · between terms

1949

Merlin Hull (WI)

Progressive → Republican · between terms

1947

Harold Hagen (MN)

Farmer-Labor → Republican · between terms

1945

Patterns

DEM → REP

22

of 52 switches

REP → DEM

6

of 52 switches

MID-TERM

30

Switched while serving, not at an election

Party switches by members of Congress, by decade, 1945 to date.
1940s
3
1950s
4
1960s
3
1970s
6
1980s
7
1990s
10
2000s
10
2010s
4
2020s
5

The largest cluster followed the 1994 election, when Republicans won both chambers: 7 Democrats became Republicans within a year — Richard Shelby (AL), Ben Campbell (CO), Nathan Deal (GA), Gregory Laughlin (TX), Billy Tauzin (LA), Mike Parker (MS), James Hayes (LA).

Since 2019 the pattern has changed: 5 of the 7 switches have been members leaving a party to become independents rather than joining the other one.

What switching parties changes

A member who switches keeps their seat. Nothing in the Constitution requires a resignation or a special election; the member next faces voters at their next scheduled election.

What does change is the party count — and with it, possibly, which party controls the chamber, chairs its committees and sets its agenda, as Jeffords showed. Independents choose which party, if either, to caucus with; see the current party breakdown.

Frequently Asked Questions

How many members of Congress have switched parties?

Since 1945, 47 members have changed party 52 times while serving: 22 from Democrat to Republican, 6 from Republican to Democrat, and 11 to independent.

Which senators have switched parties?

Joe Manchin III (WV, Democrat to Independent, 2024); Kyrsten Sinema (AZ, Democrat to Independent, 2022); Arlen Specter (PA, Republican to Democrat, 2009); Joseph Lieberman (CT, Democrat to Independent, 2007); Jim Jeffords (VT, Republican to Independent, 2001); Ben Campbell (CO, Democrat to Republican, 1995); Richard Shelby (AL, Democrat to Republican, 1994); Harry Byrd Jr. (VA, Democrat to Independent, 1971); Strom Thurmond (SC, Democrat to Republican, 1964); Wayne Morse (OR, Independent to Democrat, 1957); Wayne Morse (OR, Republican to Independent, 1951).

Who was the last member of Congress to switch parties?

Kevin Kiley of CA, from Republican to Independent, on March 9, 2026.

Does a member who switches parties have to run again?

No. They keep their seat for the rest of the term; the Constitution requires no resignation or special election. They face voters at their next scheduled election.

Source: unitedstates/congress-legislators (public domain), the party recorded for each term and mid-term change. Party names are the dataset’s own; three label-only changes (New York fusion lines and one unexplained record) are excluded.

Related Resources

Party Breakdown of Congress

Current Senate and House seats by party — majority margins, Independents, and vacancies, from live data.

What Number Congress Is This?

The current Congress, and every Congress since 1973 — party control, Speakers, laws passed and days in session.

Expelled and Censured Members of Congress

Every member the House or Senate has expelled, censured or reprimanded — and the votes it takes.

Congress by the Numbers

Average age, women in Congress, generations, tenure records, delegation sizes, and the 2026 Senate map — computed daily.