The 2006 Liberal Democrats deputy leadership election began on 2 March 2006, when the sitting Deputy Leader of the Liberal Democrats, Sir Menzies Campbell, was elected leader of the party. Campbell had been deputy leader since February 2003. The post was elected by and from the party's 63 Members of Parliament in the House of Commons, who voted on 29 March 2006. Vince Cable was elected as deputy leader in the second round.