Candidates (O)

Dave Olszta

• 2010 – United States Senate (Connecticut) (W/I) – lost
• 2020 – Colorado’s 7th congressional district (Unity) – lost

John Walter Olver

• 1992 – Massachusetts’ 1st congressional district (D) – won
• 1994 – Massachusetts’ 1st congressional district (D) – won
• 1996 – Massachusetts’ 1st congressional district (D) – won
• 1998 – Massachusetts’ 1st congressional district (D) – won
• 2000 – Massachusetts’ 1st congressional district (D) – won
• 2002 – Massachusetts’ 1st congressional district (D) – won
• 2004 – Massachusetts’ 1st congressional district (D) – won
• 2006 – Massachusetts’ 1st congressional district (D) – won
• 2008 – Massachusetts’ 1st congressional district (D) – won
• 2010 – Massachusetts’ 1st congressional district (D) – won

Dale S. Olvera

• 1992 – California’s 33rd congressional district (L) – lost

Christine Olvo

• 2020 – Florida’s 24th congressional district (I) – lost

Bernie Omann

• 1992 – Minnesota’s 7th congressional district (IR) – lost
• 1994 – Minnesota’s 7th congressional district (IR) – lost

Ilhan Abdullahi Omar

• 2018 – Minnesota’s 5th congressional district (DFL) – won
• 2020 – Minnesota’s 5th congressional district (DFL) – won
• 2022 – Minnesota’s 5th congressional district (DFL) – won

Lloyd B. Omdahl

• 1976 – North Dakota’s at large congressional district (D) – lost

Maynard J. Omerberg

• 1948 – California’s 15th congressional district (Ind. Prog.) – lost

Iro Omere

• 2022 – Texas’ 4th congressional district (D) – lost

Andrew Omholt

• 1930 – North Dakota’s 3rd congressional district (Comm.) – lost

Ella Bloor Omholt

• 1940 – Pennsylvania’s 2nd congressional district (Comm.) – lost

John Omland

• 1940 – North Dakota’s at large congressional district (I) – lost

Simon Ommerman

• 1928 – Missouri’s 5th congressional district (S) – lost

Bill Onasch

• 1982 – United States Senate (Minnesota) (SW) – lost

Dianne G. Ondusko

• 1996 – Connecticut’s 2nd congressional district (IND) – lost
• 1998 – Connecticut’s 2nd congressional district (IND) – lost

James Oneal

• 1922 – New York’s 7th congressional district (S, FL) – lost
• 1926 – New York’s 2nd congressional district (S) – lost
• 1928 – New York’s 7th congressional district (S) – lost
• 1932 – New York’s 2nd congressional district (S) – lost

Christian Onuoha

• 2020 – New Jersey’s 6th congressional district (R) – lost

Michael P. Oot

• 2008 – New York’s 23rd congressional district (D, WF) – lost

William J. Opalicky

• 2008 – Michigan’s 12th congressional district (G) – lost
• 2012 – Michigan’s 2nd congressional district (G) – lost

Jay Philip Oppenheim

• 1978 – Indiana’s 2nd congressional district (R) – lost

Orin Opperman

• 2002 – Florida’s 18th congressional district (I) – lost

Allan Opus

• 1996 – Oregon’s 4th congressional district (Pacific) – lost

Albert Oram

• 2002 – Florida’s 1st congressional district (D) – lost
• 2020 – Florida’s 1st congressional district (D) – lost

Richard Orawiec

• 1974 – Michigan’s 12th congressional district (SW) – lost

Ernest R. Orchard

• 1952 – Minnesota’s 8th congressional district (R) – lost
• 1954 – Minnesota’s 8th congressional district (R) – lost

Jack C. Orchulli

• 2004 – United States Senate (Connecticut) (R) – lost

John Ordille

• 2012 – New Jersey’s 2nd congressional district (L) – lost
• 2016 – New Jersey’s 2nd congressional district (L) – lost
• 2018 – New Jersey’s 2nd congressional district (L) – lost

Sidney L. Ordower

• 1948 – Illinois’ 6th congressional district (Prog.) – lost

Jeffrey R. Orenstein

• 1982 – Ohio’s 16th congressional district (D) – lost

Charles A. Oriez

• 1992 – Colorado’s 5th congressional district (D) – lost

Frank Orland

• 2004 – New Jersey’s 3rd congressional district (L) – lost

Matthew Orlando

• 2016 – Michigan’s 9th congressional district (L) – lost

Walter J. Orlikoski

• 1940 – Illinois’ at large congressional district (D) – lost

Steve A. Orlins

• 1992 – New York’s 3rd congressional district (D) – lost

Richard J. Orloski

• 1982 – Pennsylvania’s 15th congressional district (D) – lost
• 1990 – Pennsylvania’s 15th congressional district (D) – lost

Gregory John Orman

• 2014 – United States Senate (Kansas) (I) – lost

John M. Orman

• 1984 – Connecticut’s 4th congressional district (D) – lost

Elmer H. Ormiston

• 1958 – United States Senate (Michigan) (Proh.) – lost

Walter M. Ormsby

• 1962 – New York’s 1st congressional district (R) – lost

Matt Ornati

• 2000 – California’s 36th congressional district (NL) – lost

Robert Ornelas

• 2021 – New Mexico’s 1st congressional district (Special) (W/I) – lost

Franklin Ornstein

• 1974 – New York’s 4th congressional district (D) – lost

Bill Orozco

• 1966 – California’s 29th congressional district (R) – lost
• 1968 – California’s 29th congressional district (R) – lost

A. W. Orr

• 1942 – Texas’ 7th congressional district (R) – lost

Edwin S. Orr

• 1926 – Pennsylvania’s 9th congressional district (S) – lost

George Orr

• 1920 – New York’s 24th congressional district (S) – lost

James W. Orr

• 1964 – Texas’ 7th congressional district (R) – lost

Samuel Orr

• 1926 – New York’s 23rd congressional district (S) – lost
• 1930 – New York’s 23rd congressional district (S) – lost
• 1932 – New York’s 23rd congressional district (S) – lost
• 1934 – New York’s 23rd congressional district (S) – lost

Shawn Orr

• 2020 – Vermont’s at large congressional district (I) – lost

Jack Orswell

• 2012 – California’s 27th congressional district (R) – lost
• 2014 – California’s 27th congressional district (R) – lost
• 2016 – California’s 27th congressional district (R) – lost