Table:
text: 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%

text: United States Senate elections, 1956
Race summaries
Races leading to the 85th Congress
State_ Incumbent Party Result_ Candidates_
Florida George A. Smathers Democratic Re-elected George A. Smathers (Democratic) Unopposed
Georgia Walter F. George Democratic Retired , Democratic hold Herman E. Talmadge (Democratic) Unopposed
Idaho Herman Welker Republican Lost re-election , Democratic gain Frank Church (Democratic) 56.2% , Herman Welker (Republican) 38.7%
Illinois Everett M. Dirksen Republican Re-elected Everett M. Dirksen (Republican) 54.1% , W. Richard Stengel (Democratic) 45.7%
Indiana Homer E. Capehart Republican Re-elected Homer E. Capehart (Republican) 55.2% , Claude R. Wickard (Democratic) 44.4%
Iowa Bourke B. Hickenlooper Republican Re-elected Bourke B. Hickenlooper (Republican) 53.9% , R. M. Evans (Democratic) 46.1%
Kansas Frank Carlson Republican Re-elected Frank Carlson (Republican) 57.9% , George Hart (Democratic) 40.5%

text: United States Senate elections, 1956
Race summaries
Races leading to the 85th Congress
State_ Incumbent Party Result_ Candidates_
Kentucky Earle C. Clements Democratic Lost re-election , Republican gain Thruston Morton (Republican) 50.4% , Earle C. Clements (Democratic) 49.7%
Kentucky , Special: Class 2 Robert Humphreys Democratic Appointee retired , Winner elected to finish term ending January 3, 1961 , Republican gain John S. Cooper (Republican) 53.2% , Lawrence W. Wetherby (Democratic) 46.8%
Louisiana Russell B. Long Democratic Re-elected Russell B. Long (Democratic) Unopposed
Maryland John M. Butler Republican Re-elected John M. Butler (Republican) 53.0% , George P. Mahoney (Democratic) 47.0%
Missouri Thomas C. Hennings, Jr. Democratic Re-elected Thomas C. Hennings, Jr. (Democratic) 56.4% , Herbert Douglas (Republican) 43.6%
Nevada Alan Bible Democratic Re-elected Alan Bible (Democratic) 52.6% , Cliff Young (Republican) 47.4%

text: United States Senate elections, 1956
Race summaries
Races leading to the 85th Congress
State_ Incumbent Party Result_ Candidates_
New Hampshire Norris Cotton Republican Re-elected Norris Cotton (Republican) 64.1% , Laurence M. Pickett (Democratic) 35.9%
New York Herbert H. Lehman Democratic Retired , Republican gain Jacob K. Javits (Republican) 53.3% , Robert F. Wagner, Jr. (Democratic) 46.7%
North Carolina Sam J. Ervin, Jr. Democratic Re-elected Sam J. Ervin, Jr. (Democratic) 66.6% , Joel A. Johnson (Republican) 33.4%
North Dakota Milton R. Young Republican Re-elected Milton R. Young (Republican) 63.6% , Quentin N. Burdick (Democratic) 36.0%
Ohio George H. Bender Republican Lost re-election , Democratic gain Frank J. Lausche (Democratic) 52.9% , George H. Bender (Republican) 47.1%
Oklahoma A. S. Mike Monroney Democratic Re-elected A. S. Mike Monroney (Democratic) 55.4% , Douglas McKeever (Republican) 44.7%

text: United States Senate elections, 1956
Race summaries
Races leading to the 85th Congress
State_ Incumbent Party Result_ Candidates_
Oregon Wayne Morse Democratic Re-elected Wayne Morse (Democratic) 54.2% , Douglas McKay (Republican) 45.8%
Pennsylvania James H. Duff Republican Lost re-election , Democratic gain Joseph S. Clark (Democratic) 50.1% , James H. Duff (Republican) 49.7%
South Carolina Olin B. Johnston Democratic Re-elected Olin B. Johnston (Democratic) Unopposed
South Carolina , Special: Class 2 Thomas A. Wofford Democratic Appointee retired , Winner elected to finish term ending January 3, 1961 , Democratic hold Strom Thurmond (Democratic) Unopposed
South Dakota Francis Case Republican Re-elected Francis Case (Republican) 50.8% , Kenneth Holum (Democratic) 49.2%
Utah Wallace F. Bennett Republican Re-elected Wallace F. Bennett (Republican) 54.0% , Alonzo F. Hopkin (Democratic) 46.0%

text: United States Senate elections, 1956
Race summaries
Races leading to the 85th Congress
State_ Incumbent Party Result_ Candidates_
Vermont George D. Aiken Republican Re-elected George D. Aiken (Republican) 66.4% , Bernard G. O`Shea (Democratic) 33.6%
Washington Warren G. Magnuson Democratic Re-elected Warren G. Magnuson (Democratic) 61.1% , Arthur B. Langlie (Republican) 38.9%
West Virginia , Special: Class 1 William R. Laird, III Democratic Appointee retired , Winner elected to finish term ending January 3, 1959 , Republican gain Chapman Revercomb (Republican) 53.7% , William C. Marland (Democratic) 46.3%
Wisconsin Alexander Wiley Republican Re-elected Alexander Wiley (Republican) 58.6% , Henry W. Maier (Democratic) 41.2%

Question: Counts and returns the number of incumbents in the United States Senate election, 1956. ?