The Cheadle by-election, in Greater Manchester, England, was caused by the death of Patsy Calton, the Liberal Democrat Member of Parliament (MP) for Cheadle on 29 May 2005. The election was held on 14 July 2005.
The Liberal Democrat candidate succeeding Calton was Stockport council leader Mark Hunter. The Conservative candidate was Stephen Day (who held the seat from 1987 to 2001, and lost to Calton in the 2005 general election). In his victory speech, Hunter described the campaign of the Conservatives as 'nasty' and 'misleading'.
The campaign was marred by accusations of dirty tricks and ruthless negative campaigning, principally accusing the Conservative campaign. Both the Liberal Democrats and a local newspaper threatened legal action over inaccuracies and defamation in Conservative campaign leaflets. The most significant example was a Conservative leaflet that superimposed a headline about Hunter's voting record on crime with a headline from a local newspaper about a rape, prompting the Liberal Democrats to threaten legal action. With only 4.6% of the vote, the Labour Party candidate, Martin Miller, lost his deposit. Labour Party did not fight an energetic campaign in a seat that was a Liberal Democrat/Conservative marginal.
With the exception of the 1997 Winchester by-election, where the general election result was annulled, it was the first seat to be defended in a by-election by the Liberal Democrats since their formation in 1988. Their predecessor parties last defended a seat in a by-election at Truro in 1987.
Result.
! scope="col" colspan="2" style="width: 130px"|Party
! scope="col" style="width: 17em"|Candidate
! scope="col" style="width: 5em"|Votes
! scope="col" style="width: 3.5em"|%
! scope="col" style="width: 3.5em"| ;templatestyles src="Template:Tooltip/styles.css" / ;±%
! colspan="3" style="text-align: right; margin-right: 0.5em" | Majority
! colspan="3" style="text-align: right; margin-right: 0.5em" scope=row | Turnout
! style="text-align:right;" | Swing
Notes.
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