Emmet O'Neal | | Democratic | 1934 | Incumbent re-elected. | nowrap | |- ! | Edward W. Creal | | Democratic | 1935 | Incumbent re-elected. | nowrap | |- ! | Brent Spence | | Democratic | 1930 | Incumbent re-elected. | nowrap | |- ! | Virgil Chapman | | Democratic | 1930 | Incumbent re-elected. | nowrap | |- ! | Andrew J. May | | Democratic | 1930 | Incumbent re-elected. | nowrap | |- ! | Joe B. Bates | | Democratic | 1930 | Incumbent re-elected. | nowrap | |- ! | John M. Robsion | | Republican | 1934 | Incumbent re-elected. | nowrap | |} Louisiana Several close allies of former governor Huey Long were defeated in primaries by reform candidates. |- ! | Joachim O. Fernandez | | Democratic | 1930 | | Incumbent lost renomination.New member elected.Democratic hold. | nowrap | |- ! | Paul H. Maloney | | Democratic | 1930 | | Incumbent lost renomination.New member elected.Democratic hold. | nowrap | |- ! | Robert L. Mouton | | Democratic | 1936 | | Incumbent lost renomination.New member elected.Democratic hold. | nowrap | |- ! | Overton Brooks | | Democratic | 1936 | Incumbent re-elected. | nowrap | |- ! | Newt V. Mills | | Democratic | 1936 | Incumbent re-elected. | nowrap | |- ! | John K. Griffith | | Democratic | 1936 | | Incumbent lost renomination.New member elected.Democratic hold. | nowrap | |- ! | Rene L. De Rouen | | Democratic | 1927 | | Incumbent retired.New member elected.Democratic hold. | nowrap | |- ! | A. Leonard Allen | | Democratic | 1936 | Incumbent re-elected. | nowrap | |} Maine |- ! | James C. Oliver | | Republican | 1936 | Incumbent re-elected. | nowrap | |- ! | Margaret Chase Smith | | Republican | 1940 | Incumbent re-elected. | nowrap | |- ! | Ralph Owen Brewster | | Republican | 1934 | | Incumbent retired to run for U.S. senator.New member elected.Republican hold. | nowrap | |} Maryland |- ! | David Jenkins Ward | | Democratic | 1939 | Incumbent re-elected. | nowrap | |- ! | William P. Cole Jr. | | Democratic | 1930 | Incumbent re-elected. | nowrap | |- ! | Thomas D'Alesandro Jr. | | Democratic | 1938