1918 United States Senate election in Minnesota

1918 United States Senate election in Minnesota
	County results; Nelson: 50–60% 60–70% 70-80%; Calderwood: 50-60% 60-70%
U.S. senator before election; Knute Nelson; Republican	Elected U.S. Senator ; Knute Nelson; Republican

The 1918 United States Senate election in Minnesota took place on November 5, 1918. It was the first election for Minnesota's Class 2 seat in the United States Senate, and the second U.S. Senate election in Minnesota overall, held after the ratification of the Seventeenth Amendment to the United States Constitution, which established the popular election of United States Senators. Incumbent U.S. Senator Knute Nelson of the Republican Party of Minnesota easily defeated his challenger in the general election, Willis Greenleaf Calderwood of the National Party, to win a fourth term in the Senate.

Republican primary

Knute Nelson, Incumbent U.S. Senator since 1895
James A. Peterson, Minneapolis attorney, former Hennepin County Attorney (1897–1899), former State Representative from the 42nd district (1901–1903), Republican candidate for U.S. Senate in 1912^[1]

Republican primary election results^[2]
Party		Candidate	Votes	%
	Republican	Knute Nelson (Incumbent)	229,923	71.99%
	Republican	James A. Peterson	89,464	28.01%
Total votes			319,387	100.00%

Willis G. Calderwood, state chair of the Prohibition Party, Prohibition nominee for state House District 30 in 1894, for state House District 39 in 1904, 1906, 1908, and 1910, for the at-large U.S. House seat in 1912, for Governor in 1914, and for the U.S. Senate in 1916; Farmer-Labor candidate for Lieutenant Governor in 1924^[3]

Special election results^[4]
Party		Candidate	Votes	%
	Republican	Knute Nelson (Incumbent)	206,428	60.05%
	National	Willis G. Calderwood	137,334	39.95%
Total votes			343,762	100.00%
Majority			69,094	20.10%
	Republican hold

^ University of Minnesota Libraries, University of Minnesota. "1918 Minnesota U.S. Senate Republican Primary". Minnesota Historical Election Archive. Archived from the original on August 23, 2021. Retrieved August 23, 2021.
^ "Primary Election Results of election held June 17th, 1918" (PDF). Minnesota Legislature.
^ University of Minnesota Libraries, University of Minnesota. "1918 Minnesota U.S. Senate General Election". Minnesota Historical Election Archive. Archived from the original on August 23, 2021. Retrieved August 23, 2021.
^ "MN US Senate, 1918". ourcampaigns.com.

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