Turnout

In the primaries, 2,647,467 ballots were cast (1,503,706 Democratic and 1,143,761 Republican).^[1]

In the general election, 4,262,196 ballots were cast.^[1]

United States President

Illinois voted for the Democratic ticket of Franklin D. Roosevelt and Henry A. Wallace.

United States Senate

Republican Charles W. Brooks unseated Democrat James M. Slattery, who had been appointed to the seat left vacant by the death in office of Democrat J. Hamilton Lewis.

United States House

All 27 Illinois seats in the United States House of Representatives were up for election in 1940.

Republicans flipped six Democratic-held seats, making the composition of Illinois' House delegation 16 Republicans and 11 Democrats.

Governor

1940 Illinois gubernatorial election

November 5, 1940

Nominee Dwight H. Green Harry B. Hershey Party Republican Democratic Popular vote 2,197,778 1,940,833 Percentage 52.93% 46.74%

County Results Green:      40–50%      50–60%      60–70%      70–80% Hershey:      50–60%      60–70%

Governor before election Henry Horner (before primary) Democratic John Henry Stelle (before general election) Democratic Elected Governor Dwight H. Green Republican

Before the primary, incumbent governor Henry Horner, a Democrat, opted not to seek a third term. In October, before the general election, his death in office made John Henry Stelle assume the governorship. However, Stelle had previously failed to win the Democratic nomination in the primary.

Republican Dwight H. Green won the election.

Lieutenant governor

1940 Illinois lieutenant gubernatorial election

November 5, 1940

Nominee Hugh W. Cross Louie E. Lewis Party Republican Democratic Popular vote 2,073,679 1,955,834 Percentage 51.27% 48.36%

Lieutenant Governor before election John Henry Stelle (before primary) Democratic Party Vacant (before general election) Elected Lieutenant Governor Hugh W. Cross Republican

Incumbent lieutenant governor John Henry Stelle, a Democrat, did not seek reelection to a second term, instead opting to run for governor. Republican Hugh W. Cross was elected to succeed him.

Attorney general

1940 Illinois Attorney General election

November 5, 1940

Nominee George F. Barrett Harold G. Ward Party Republican Democratic Popular vote 2,061,807 1,956,744 Percentage 51.12% 48.51%

Attorney General before election John Edward Cassidy Democratic Elected Attorney General George F. Barrett Republican

Incumbent Attorney General John Edward Cassidy, a Democrat appointed in 1938 after fellow Democrat Otto Kerner Sr. resigned to accept a federal judgeship, did not seek reelection to a full term. Republican George F. Barrett was elected to succeed him.

Secretary of State

1940 Illinois Secretary of State election

November 5, 1940

Nominee Edward J. Hughes Justus L. Johnson Party Democratic Republican Popular vote 2,095,698 1,962,405 Percentage 51.46% 48.19%

County results Hughes:      40–50%      50–60%      60–70% Johnson:      40–50%      50–60%      60–70%      70–80%

Secretary of State before election Edward J. Hughes Democratic Elected Secretary of State Edward J. Hughes Democratic

Incumbent second-term Secretary of State Edward J. Hughes, a Democrat, was reelected.

Auditor of Public Accounts

1940 Illinois Auditor of Public Accounts election

November 5, 1940

Nominee Arthur C. Lueder John C. Martin Party Republican Democratic Popular vote 2,027,571 1,988,366 Percentage 50.30% 49.33%

Auditor of Public Accounts before election Edward J. Barrett Democratic Elected Auditor of Public Accounts Arthur C. Lueder Republican

Incumbent third-term Auditor of Public Accounts Edward J. Barrett, lost renomination in the Democratic primary. Republican Arthur C. Lueder was elected to succeed him.

Treasurer

1940 Illinois State Treasurer election

November 5, 1940

Nominee Warren Wright Homer Mat Adams Party Republican Democratic Popular vote 2,030,513 1,983,667 Percentage 50.40% 49.24%

Treasurer before election Louie E. Lewis Democratic Elected Treasurer Warren Wright Republican

Incumbent first-term Treasurer Louie E. Lewis, a Democrat, did not seek reelection, instead running for lieutenant governor. Republican Warren Wright was elected to succeed him in office.

State Senate

Seats of the Illinois Senate were up for election in 1940. Republicans flipped control of the chamber.

State House of Representatives

Seats in the Illinois House of Representatives were up for election in 1940. Republicans retained control of the chamber.

University of Illinois trustees

1940 University of Illinois trustees elections

November 5, 1940
4 out of 9 seats on the University of Illinois Board of Trustees 5 seats needed for a majority
Majority party Minority party   Party Democratic Republican Seats before 9 0 Seats after 5 4 Seat change 4 4 Popular vote 7,717,234A 7,900,386½[B] Percentage 49.27%[C] 50.44%[D] Swing 5.99% 2.59% Seats up 4 0 Races won 0 4 [1][4][5][6][7]

An election was held for three of the nine seats for Trustees of University of Illinois to six year terms, and a special election was held to fill the partial term of a seat that was vacated.^[1] Republicans swept all four seats in the two elections.^[1] The election was for six-year terms.

Regular election

1940 University of Illinois trustees (regular election)

November 5, 1940
3 out of 9 seats on the University of Illinois Board of Trustees
Majority party Minority party   Party Republican Democratic Popular vote 5,957,269 5,806,332 Percentage 50.44% 49.16% Swing 2.59% 2.61% Seats up 0 3 Races won 3 0 [1][6]

An election was held for three six-year terms to the board.

Former two-term Republican member Helen M. H. Grigsby was returned to the board.^[1][7] New Republican members John R. Fornof and Park Livingston were elected to the board.^[1][7]

Incumbent first-term Democrat Marie Coyle Plumb lost reelection.^[1][7]

First-term Democrats Oscar G. Mayer Sr. and Harold Pogue did not seek reelection.^[1][7]

Marie Coyle Plumb was listed on the ballot as "Mrs. Glenn E. Plumb", and Beulah Campbell was listed as "Belulah (Mrs. Bruce A.) Campbell".^[1][7]

University of Illinois trustees election^[1][7]

Party		Candidate	Votes	%
	Republican	Park Livingston	2,017,302½	17.08
	Republican	Helen Mathews Grigsby	1,972,433	16.70
	Republican	John R. Fornof	1,967,534	16.66
	Democratic	W. E. C. Clifford	1,954,221½	16.55
	Democratic	Beulah (Mrs. Bruce A.) Campbell	1,941,938½	16.44
	Democratic	Mrs. Glenn E. Plumb	1,910,171½	16.17
	Socialist	Kate M. Ward	8,286	0.07
	Socialist	Jack Sessions	8,001	0.07
	Socialist	Eva S. Cowan	7,927	0.07
	Prohibition	Mildred E. Young	7,631½	0.07
	Prohibition	Maude Swits Stowell	7,420½	0.06
	Prohibition	Lois Gilbert Krandell	7,270½	0.06
	Write-in	Others	39	0.00
Total votes			11,810,176½	100

Special election

1940 University of Illinois trustee special election

November 5, 1940

Nominee Chester R. Davis Kenney E. Williamson Party Republican Democratic Popular vote 1,943,117 1,910,902 Percentage 50.42% 49.58%

Trustee before election Kenney E. Williamson Democratic Elected Trustee Chester R. Davis Republican

A special election was held to fill the term left vacant by the death in office of Democrat Louis Conrad Moschel in 1940.^[1][7] Republican Chester R. Davis was elected, defeating incumbent Kenny E. Williamson (who had been appointed to hold the seat after the death of Moschel).^[1][7]

University of Illinois trustee special election^[1][7]

Party		Candidate	Votes	%
	Republican	Chester R. Davis	1,943,117	50.42
	Democratic	Kenney E. Williamson (incumbent)	1,910,902	49.58
Total votes			3,854,019	100

Judicial elections

On June 3, 1940, an election was held for judges of the Superior Court of Cook County.

On November 5, 1940, an election was held to fill a vacancy on the Eighth Judicial Circuit.

Ballot measure

A legislatively referred state statute was brought before the voters.