1940 United States Senate election in Wyoming

← 1934

November 5, 1940

1946 →


Nominee	Joseph C. O'Mahoney	Milward Simpson
Party	Democratic	Republican
Popular vote	65,022	45,682
Percentage	58.74%	41.26%

U.S. senator before election

Joseph C. O'Mahoney
Democratic

Elected U.S. Senator

Joseph C. O'Mahoney
Democratic

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The 1940 United States Senate election in Wyoming took place on November 5, 1940. Democratic Senator Joseph C. O'Mahoney ran for re-election to a second full term. He faced Republican Milward Simpson, a member of the University of Wyoming Board of Trustees and a former State Representative, in the general election. Though the presidential election in Wyoming was relatively close, O'Mahoney outperformed President Franklin D. Roosevelt's narrow win, and defeated Simpson in a landslide to win his second term.

Democratic primary

Candidates

Joseph C. O'Mahoney, incumbent U.S. Senator
Cecil W. Clark, former Weston County Prosecuting Attorney^[1]

Results

Democratic primary^[2]
Party		Candidate	Votes	%
	Democratic	Joseph C. O'Mahoney (inc.)	25,473	90.45%
	Democratic	Cecil W. Clark	2,688	9.55%
Total votes			28,161	100.00%

Republican primary

Candidates

Milward Simpson, member of the University of Wyoming Board of Trustees, former State Representative
Harry B. Henderson, Jr., State Senator^[3]
Charles E. Winter, former U.S. Congressman
Irving W. Dinsmore, former State Senator^[4]
R. R. Crow, State Representative^[5]

Results

Republican primary^[2]
Party		Candidate	Votes	%
	Republican	Milward Simpson	12,014	37.47%
	Republican	Harry B. Henderson, Jr.	8,816	27.49%
	Republican	Charles E. Winter	6,128	19.11%
	Republican	Irving W. Dinsmore	2,910	9.08%
	Republican	R. R. Crow	2,197	6.85%
Total votes			32,065	100.00%

General election

Results

1940 United States Senate election in Wyoming^[2]
Party		Candidate	Votes	%	±%
	Democratic	Joseph C. O'Mahoney (inc.)	65,022	58.74%	+2.11%
	Republican	Milward Simpson	45,682	41.26%	-1.69%
Majority			19,340	17.47%	+3.80%
Turnout			110,704
	Democratic hold

References

^ "Newcastle Attorney Enters Campaign for Senate Seat". Casper Star-Tribune. Casper, Wyo. March 18, 1940. p. 1.
^ ^a ^b ^c Hunt, Lester C. (1941). 1941 Official Directory of Wyoming and Election Returns for 1940. Casper, Wyo.: Prairie Publishing Co. pp. 70–74.
^ "Harry Henderson In Senate Race". Casper Star-Tribune. Casper, Wyo. February 29, 1940. p. 1.
^ "I. W. DInsmore of Rawlins Enters Race for Senate". Casper Star-Tribune. Casper, Wyo. March 20, 1940. p. 1.
^ "Saratoga Man Enters Race for U.S. Senate: R. R. Crow Is One of Five Republican Candidates; Other Filings Announced". Casper Star-Tribune. Casper, Wyo. July 22, 1940. p. 1.

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