The 1980 Delaware lieutenant gubernatorial election was held on 4 November 1980 in order to elect the lieutenant governor of Delaware. Republican nominee and former member of the Delaware Senate Mike Castle defeated Democratic nominee Thomas B. Sharp, Libertarian nominee Margaret R. Buchanan and American nominee Donald G. Gies.
General election.
On election day, 4 November 1980, Republican nominee Mike Castle won the election by a margin of 40,603 votes against his foremost opponent Democratic nominee Thomas B. Sharp, thereby gaining Republican control over the office of lieutenant governor. Castle was sworn in as the 20th lieutenant governor of Delaware on 20 January 1981.
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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