1980 United States Senate election in Iowa

1980 United States Senate election in Iowa
	County results ; Grassley: 50-60% 60-70% 70-80% ; Culver: 50–60% 60–70%
U.S. senator before election; John Culver; Democratic	Elected U.S. Senator ; Chuck Grassley; Republican

The 1980 United States Senate election in Iowa was held on November 4, 1980. Incumbent Democratic United States Senator John Culver ran for reelection to a second term, but lost to Republican nominee Chuck Grassley, the United States Congressman from Iowa's 3rd congressional district. This election marked the beginning of eight consecutive victories for Grassley in the Senate. It remains the closest election of his Senate career.^{[citation needed]}

Democratic primary

Democratic primary results ^[1]
Party		Candidate	Votes	%
	Democratic	John Culver (incumbent)	95,656	99.95%
	Democratic	Write-ins	52	0.05%
Total votes			95,708	100.00%

Republican primary results^[1]
Party		Candidate	Votes	%
	Republican	Chuck Grassley	170,120	65.54%
	Republican	Tom Stoner	89,409	34.45%
	Republican	Write-ins	34	0.01%
Total votes			259,563	100.00%

United States Senate election in Iowa, 1980^[2]
Party		Candidate	Votes	%	±%
	Republican	Chuck Grassley	683,014	53.49%	6.21
	Democratic	John Culver (incumbent)	581,545	45.54%	6.50
	Independent	Garry De Young	5,858	0.46%	N/A
	Libertarian	Robert V. Hengerer	4,233	0.33%	N/A
	Independent	John Ingram Henderson	2,336	0.18%	N/A
Majority			101,469	7.95%	+3.19%
Turnout			1,772,983
	Republican gain from Democratic		Swing

^ ^a ^b Synhorst, Melvin. "SUMMARY OF OFFICIAL CANVASS OF VOTES CAST IN IOWA PRIMARY ELECTION JUNE 3, 1980" (PDF). Iowa Secretary of State. State of Iowa. Retrieved May 20, 2022.
^ "STATISTICS OF THE PRESIDENTIAL AND CONGRESSIONAL ELECTION OF NOVEMBER 4, 1980" (PDF). Office of the Clerk, U.S. House of Representatives. House of Representatives. Retrieved May 20, 2022.