The 1966 Quebec general election was held on June 5, 1966, to elect members of the Legislative Assembly of Quebec, Canada. The Union Nationale (UN), led by Daniel Johnson, Sr, defeated the incumbent Quebec Liberal Party, led by Jean Lesage.
In terms of the number of seats won, the election was one of the closest in recent history, with the UN winning 56 seats to the Liberals' 50. Generally, Quebec's first past the post electoral system tends to produce strong disparities in the number of seats won even if the popular vote is fairly close. In this case, the most popular party did not win the most seats in the chamber. The Liberals won 6.5% more votes, but were denied a third term because the rural part of the province, where the Union Nationale did well, were slightly over-represented in the legislature.
The victory of the UN over the popular Lesage government was a surprise to many observers. Johnson's campaign was likely helped by his position that Quebec should get a better deal within the Canadian confederation, or should separate if it is unable to do so. In this sense, the forces of Quebec nationalism unleashed by the Quiet Revolution begun by Lesage may have contributed to his defeat, as many rural voters felt chagrin at the rapid pace of reform under the Liberals.
The pro-independence "Rassemblement pour l'indépendance nationale" and "Ralliement national" (formed from splinter groups out of the RIN and the "Ralliement des créditistes") obtained a combined total of just under 9% of the popular vote (but no seats).
This was the last election for the "Legislative Assembly of Quebec". Legislation was passed to replace the bicameral system of Legislative Assembly and Legislative Council of Quebec with a single National Assembly of Quebec, effective December 31, 1968.
Daniel Johnson died in office in 1968, and was succeeded by Jean-Jacques Bertrand. Johnson's sons, Pierre-Marc and Daniel Jr, each later served as Premier of Quebec.
Redistribution of ridings.
A 1965 Act increased the number of MPPs from 95 to 108 through the following changes:
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Results.
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Synopsis of results.
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 ;templatestyles src="Legend/styles.css" / ;  = open seat
 ;templatestyles src="Legend/styles.css" / ;  = turnout is above provincial average
 ;templatestyles src="Legend/styles.css" / ;  = winning candidate was in previous Legislature
 ;templatestyles src="Legend/styles.css" / ;  = incumbent had switched allegiance
 ;templatestyles src="Legend/styles.css" / ;  = previously incumbent in another riding
 ;templatestyles src="Legend/styles.css" / ;  = not incumbent; was previously elected to the Legislature
 ;templatestyles src="Legend/styles.css" / ;  = incumbency arose from byelection gain
 ;templatestyles src="Legend/styles.css" / ;  = other incumbents renominated
 ;templatestyles src="Legend/styles.css" / ;  = previously an MP in the House of Commons of Canada
 ;templatestyles src="Legend/styles.css" / ;  = multiple candidates
References.
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