The 1940 Missouri State Auditor election was held on 5 November 1940 in order to elect the state auditor of Missouri. Democratic nominee and incumbent state auditor Forrest Smith defeated Republican nominee J. T. Waddill and Socialist nominee Helen Nichols.
General election.
On election day, 5 November 1940, Democratic nominee Forrest Smith won re-election by a margin of 105,766 votes against his foremost opponent Republican nominee J. T. Waddill, thereby retaining Democratic control over the office of state auditor. Smith was sworn in for his third term on 13 January 1941.
Results.
! scope="col" colspan="2" style="width: 15em" |Party
! scope="col" style="width: 17em" |Candidate
! scope="col" style="width: 5em" |Votes
! scope="col" style="width: 3.5em" |%
! colspan="3" style="text-align:right;" | Total votes
References.
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