and the Liberal Democrats, and lasted for five days. There was an aborted attempt to put together a Labour/Liberal Democrat coalition (although 11 seats from other smaller parties would have been required). To facilitate this, Gordon Brown announced on the evening of Monday 10 May that he would resign as Leader of the Labour Party. Realising that a deal between the Conservatives and the Liberal Democrats was imminent, Brown resigned the next day, on Tuesday 11 May, as Prime Minister, marking the end of 13 years of Labour government. This was accepted by Queen Elizabeth II, who then invited David Cameron to form a government in her name and become Prime Minister. Just after midnight on 12 May, the Liberal Democrats approved the agreement "overwhelmingly", sealing a coalition government of Conservatives and Liberal Democrats. None of the three main party leaders had previously led a general election campaign, a situation which had not occurred since the 1979 election. During the campaign, the three main party leaders engaged in the first televised debates. The Liberal Democrats achieved a breakthrough in opinion polls after the first debate, in which their leader Nick Clegg was widely seen as the strongest performer. Nonetheless, on polling day their share of the vote increased by only 1%, with a net loss of five seats. This was still the Liberal Democrats' largest popular vote since the party's creation in 1988; they found themselves in a pivotal role in the formation of the new government. The share of votes for parties other than Labour or the Conservatives was 35%, the largest since the 1918 general election. In terms of votes it was the most "three-cornered" election since 1923, as well as in terms of seats since 1929. The Green Party of England and Wales won its first ever seat in the House of Commons, and the Alliance Party of Northern Ireland also gained its first elected member. The general election saw a 5.1% national swing from Labour to the Conservatives, the third-largest since 1945. The result in one constituency, Oldham East and Saddleworth, was subsequently declared void on petition because of illegal practices during the campaign, the first such instance since 1910. 150 new MPs were elected at the election. Notable newcomers who were elected to parliament in 2010 included future Conservative Prime Minister Liz Truss, future Home Secretaries Priti Patel and Sajid Javid, future Leader of the