parties went into the general election having changed leaders since 2005. David Cameron became Conservative leader in December 2005, replacing Michael Howard. Gordon Brown succeeded Tony Blair as leader of the Labour Party and Prime Minister in June 2007. Nick Clegg was elected as leader of the Liberal Democrats in December 2007, succeeding Menzies Campbell who had replaced Charles Kennedy in January 2006. The last time all three main parties went into a general election with new leaders was in the 1979 election, when James Callaghan as Labour leader, Margaret Thatcher for the Conservatives, and David Steel with the then-Liberal Party took to the polls. The prospect of a coalition or minority government was being considered well before polling day. Gordon Brown made comments about the possibility of a coalition in January 2010. In 2009, it was reported that senior civil servants were to meet with the Liberal Democrats to discuss their policies, an indication of how seriously the prospect of a hung parliament was being taken. Nick Clegg and Menzies Campbell had continued the position of Charles Kennedy of not being prepared to form a coalition with either main party and of voting against any Queen's Speech unless there was an unambiguous commitment in it to introduce proportional representation. Other parties Other parties with representation at Westminster after the previous general election included the Scottish National Party, with six parliamentary seats, Plaid Cymru from Wales with three seats, and Respect – The Unity Coalition and Health Concern, each of which held one parliamentary seat in England. Since that election, the SNP had won the 2007 Scottish Parliament elections and gained control of the Scottish Government, and also won the largest share of the 2009 European Parliament election vote in Scotland. In Wales, the Labour Party remained the largest party in the Welsh Assembly, although Plaid Cymru increased their share of the vote and formed a coalition government with Labour. In 2009 the Ulster Unionist Party and the Conservative Party announced they had formed an electoral alliance whereby the two parties would field joint candidates for future elections under the banner of "Ulster Conservatives and Unionists – New Force". However, this caused the sole UUP MP Lady Sylvia Hermon to resign from the party on 25 March 2010, leaving them with no representation at Westminster for the first time in their history. Many constituencies were contested by other, smaller parties.