As Theresa May fires the starting gun on the scramble to be the next Tory leader, history shows that the favourite at the start of the race rarely ends up the winner.
June 2016
Favourite: Boris Johnson
A short, treacherous Conservative leadership campaign followed David Cameron’s decision to step down the day after the EU referendum.
The bookies’ favourite, Boris Johnson, stunned supporters by announcing he would not run at a press conference called to declare his candidacy. Minutes earlier, his running partner and Oxford University chum Michael Gove had unexpectedly announced he would stand and was expected to absorb many of Johnson’s votes.
MPs who might once have voted for Gove turned on him and he fell out of the race. It left the field open to Theresa May, who gained the support of half of Conservative MPs before the first ballot.
May’s remaining rival, Andrea Leadsom, dropped out after she gave an interview widely interpreted as criticising May for not having children. May was anointed by a cheering 1922 Committee.
Winner: Theresa May
December 2005

Favourite: David Davis
David Davis, the future former Brexit secretary, was the runaway favourite to lead the Tories after a third general election defeat at the hands of Tony Blair’s Labour in May 2005.
Michael Howard, who had pledged to stand down, set a leadership election for December, giving months for Davis’s main rival, Liam Fox, and the relatively unknown David Cameron to gather support.
Cameron’s fortunes improved further in October when he and Davis launched their campaigns on the same day. Cameron spoke without notes and urged supporters to join him “on a wonderful journey” to win over a new Tory generation. It was a speech that won admirers from the media and the Tory faithful.
In contrast, Davis’s launch was seen as tired and stage managed. A week later, Davis gave another heavily criticised speech at party conference. The tide had turned and Cameron became the new favourite.
Davis received more first preference votes than Cameron in the first round, but lost after Kenneth Clarke and Liam Fox’s second and third preferences were redistributed.
Winner: David Cameron
November 1990
Favourite: Michael Heseltine
In the aftermath of Margaret Thatcher’s decision to withdraw from a leadership challenge by Michael Heseltine, most observers believed he was an unbeatable candidate.

Heseltine’s supporters briefed newspapers claiming they were confident they had momentum entering a second ballot. The foreign secretary, Douglas Hurd, and the relatively unknown chancellor, John Major, put their names forward to challenge him.
Major’s team made much of his humble beginnings, which played well with party members. It was seen as a mistake when Heseltine, a successful publisher, was photographed at his country mansion.
Major, who had absented himself from involvement in the first ballot because of toothache, was soon seen as having the potential to lead the Conservatives to another consecutive general election victory.
Winner: John Major
February 1975

Favourite: Edward Heath
Not only was Margaret Thatcher an outside bet to become the Conservative party leader in 1975, she only became a candidate because her mentor made an inappropriate speech about eugenics.
In the aftermath of Labour’s 1974 election victory, Keith Joseph announced he would stand against the incumbent and bookies’ favourite Edward Heath.
A week after his declaration, he was forced to drop out after saying that “low intelligence women” were giving birth to a high proportion of children. “The balance of our population, our human stock is threatened,” he told an audience.
Desperate for a replacement candidate, hard-right allies encouraged Thatcher to stand instead. She was the third favourite behind another candidate from the right, Edward du Cann.
Du Cann was then forced to drop out after a government report criticised the management of a bankrupt bank of which he was a director. After a lacklustre campaign from Heath, Thatcher beat him in the first round by 130 votes to 119.
Heath’s supporters could have stopped her leadership challenge if they had coalesced around a single candidate in the second round, Thatcher’s biographer Hugo Young wrote. Instead, three Heath-ites – Geoffrey Howe, James Prior and James Peyton – put their names forward, allowing Thatcher to win with ease.
Winner: Margaret Thatcher