| | Charles L. Weltner | | Democratic | 1962 | Incumbent re-elected. | nowrap | |- | | John FlyntRedistricted from 4th | | Democratic | 1954 | Incumbent re-elected. | nowrap | |- | | John William Davis | | Democratic | 1960 | Incumbent re-elected. | nowrap | |- | | J. Russell Tuten | | Democratic | 1962 | Incumbent re-elected. | nowrap | |- | | Phillip M. Landrum | | Democratic | 1952 | Incumbent re-elected. | nowrap | |- | rowspan=2 | | Robert Grier Stephens Jr. | | Democratic | 1960 | Incumbent re-elected. | rowspan=2 nowrap | |- | Carl VinsonRedistricted from 6th | | Democratic | 1914 | | Incumbent retired.Democratic loss. |} Hawaii |- | | Spark Matsunaga | | Democratic | 1962 | Incumbent re-elected. | rowspan=2 nowrap | |- | | Thomas Gill | | Democratic | 1962 | | Incumbent retired to run for U.S. Senator.New member elected.Democratic hold. |} Idaho |- | | Compton I. White Jr. | | Democratic | 1962 | Incumbent re-elected. | nowrap | |- | | Ralph R. Harding | | Democratic | 1960 | | Incumbent lost re-election.New member elected.Republican gain. | nowrap | |} Illinois |- | | William L. Dawson | | Democratic | 1942 | Incumbent re-elected. | |- | | Barratt O'Hara | | Democratic | 19481950 1952 | Incumbent re-elected. | |- | | William T. Murphy | | Democratic | 1958 | Incumbent re-elected. | |- | | Ed Derwinski | | Republican | 1958 | Incumbent re-elected. | |- | | John C. Kluczynski | | Democratic | 1950 | Incumbent re-elected. | |- | | Thomas J. O'Brien | | Democratic | 1942 | | Incumbent died in office.New member elected.Democratic hold. | |- | | Roland V. Libonati | | Democratic | 1957 | | Incumbent retired.New member elected.Democratic hold. | |- | | Dan Rostenkowski | | Democratic | 1958 | Incumbent re-elected. | |- | | Edward Rowan Finnegan | | Democratic | 1960 | | Incumbent retired.New member elected.Democratic hold. | |- | | Harold R. Collier | | Republican | 1956 | Incumbent re-elected. | |- | | Roman Pucinski | | Democratic | 1958 | Incumbent re-elected. | |- | | Robert McClory | | Republican | 1962 | Incumbent re-elected. | |- | |