Editing By-election (section)

=== Direct effects ===

By-elections can be crucial when the ruling party has only a small majority. In [[parliamentary system]]s, party discipline is often so strong that the governing party or coalition can only lose a [[vote of no confidence]] after losing enough supporters, whether by floor-crossing or through losing by-elections, for it to become a [[minority government]]. Examples are the [[Callaghan Ministry|Labour government of James Callaghan 1976–1979]] and [[Second Major ministry|Conservative government of John Major 1992–1997]]. In the [[United States Senate]], [[2010 United States Senate special election in Massachusetts|Scott Brown's election]] in 2010 ended the [[filibuster]]-proof [[supermajority]] formerly enjoyed by [[Democratic Party (United States)|Democrats]].

By-elections can also be important if a minority party needs to gain one or more seats in order to gain [[official party status]] or the [[balance of power (parliament)|balance of power]] in a minority or coalition situation. For example, [[Andrea Horwath]]'s win in an [[Ontario]] provincial by-election in 2004 allowed the [[Ontario New Democratic Party]] to regain official party status with important results in terms of parliamentary privileges and funding.

In Australia, a by-election in 1996 in the [[Queensland]] state electoral district of [[Electoral district of Mundingburra|Mundingburra]] overturned the results of the [[1995 Queensland state election|1995 state election]]. In that election, held in July 1995, Wayne Goss and his [[Queensland Labor Party|Labor Party]] had won by a slim 45-seat majority in a 89-seat parliament. The seat of Mundingburra had been awarded to the Labor Party on the basis of a majority of 16 votes. However, in December 1995 the Court of Disputed Returns threw out the result in Mundingburra after it was found that 22 overseas military personnel had been denied the chance to vote. Consequently, a by-election for Mundingburra was held in February 1996, in which the electorate was won by the opposition [[Liberal National Party of Queensland|Liberal Party]], pushing the Goss government into minority. A vote of no confidence in the government was then passed by the opposition, with the support of Independent [[Liz Cunningham]]. Following the no confidence vote,  [[Rob Borbidge]] the leader of the [[Queensland National Party|Nationals]] the senior partner in the coalition became premier until his government's defeat in the [[1998 Queensland state election|1998 state election]].