The 1840 Missouri lieutenant gubernatorial election was held on 3 August 1840 in order to elect the lieutenant governor of Missouri. Democratic nominee Meredith Marmaduke won the election as he ran unopposed. The exact results of the election are unknown.
General election.
On election day, 3 August 1840, Democratic nominee Meredith Marmaduke won the election as he ran unopposed, thereby retaining Democratic control over the office of lieutenant governor. Marmaduke was sworn in as the 6th lieutenant governor of Missouri on 16 November 1840.
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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