Connaughton was born in Mountbellew, County Galway. He was educated at St. Jarlath's Vocational School, Mountbellew, and Mountbellew Agricultural College where he did an IMI Management Course. Connaughton first held political office in 1979, when he became a member of Galway County Council. He served on that authority on two occasions between 1979 and 1985, and again from 1991 to 2003.
He was an unsuccessful candidate at the 1975 Galway North-East by-election and the 1977 general election.[2] He was elected to Seanad Éireann as a Senator for the Agricultural Panel in 1977. Connaughton was first elected to Dáil Éireann at the 1981 general election as a Fine Gael TD for Galway East, and was returned at every subsequent election until his retirement in 2011.[2] Between 1982 and 1987, Fine Gael were in government and Connaughton served as Minister of State at the Department of Agriculture with special responsibility for Land Structure and Development. Following the parties return to opposition, he was Fine Gael Spokesperson on Energy and Western Development and Chairman of the Political Affairs Committee between 1993 and 1997.
Between 1997 and 2000, he was Spokesman on Agriculture and Food. He was Fine Gael front bench Spokesperson on Marine, Natural Resources and Energy from June 2000 to February 2001. In Enda Kenny's Front Bench reshuffle in 2004 Connaughton became Spokesperson on Regional Development and Regional Affairs. He has also served as spokesman on a range of portfolios including Agriculture; Social Welfare; Defence and Tourism; and Older People during his political career.