United States Senate elections, 1956 Race summaries Races leading to the 85th Congress

| State_ | Incumbent | Party | Result_ | Candidates_ |
|---|---|---|---|---|
| Alabama | Lister Hill | Democratic | Re-elected | Lister Hill (Democratic) Unopposed |
| Arizona | Carl Hayden | Democratic | Re-elected | Carl Hayden (Democratic) 61.4% , Ross F. Jones (Republican) 38.6% |
| Arkansas | J. William Fulbright | Democratic | Re-elected | J. William Fulbright (Democratic) 83.0% , Ben C. Henley (Republican) 17.0% |
| California | Thomas H. Kuchel | Republican | Re-elected | Thomas H. Kuchel (Republican) 54.0% , Richard Richards (Democratic) 45.6% , Ray Gourley (Prohibition) 0.4% |
| Colorado | Eugene D. Millikin | Republican | Retired , Democratic gain | John A. Carroll (Democratic) 50.2% , Dan Thornton (Republican) 49.8% |
| Connecticut | Prescott S. Bush | Republican | Re-elected | Prescott S. Bush (Republican) 54.8% , Thomas J. Dodd (Democratic) 43.1% |