Boris Johnson is the favourite to be the new prime minister in what is likely to be a crowded field of MPs hoping to take over as Conservative leader.
The former London mayor and leader of the leave campaign took an early lead with the bookmakers after years of speculation about his ambitions to succeed David Cameron.
Theresa May, the home secretary, is the leading potential candidate from the remain camp, while other Brexit MPs such as Andrea Leadsom, Priti Patel and Dominic Raab might also fancy their chances.
Tory modernisers are also pushing Amber Rudd, the energy secretary who clashed with Johnson during a television debate, to run for the leadership.
MPs are expected to start putting their names forward within days to the 1922 committee of backbenchers, ready for the parliamentary party to whittle this down to two names.
The highly Eurosceptic party membership, which numbers about 150,000, will then have the final say on the list of two.
Johnson is very likely to be on that shortlist, given his leading role in delivering an out vote on behalf of about 130 Conservative MPs who wanted Brexit.
His stock has risen sharply during the campaign, which has boosted support among the grassroots and suggested he has appeal among a wide constituency in the country as well.
Johnson has always dodged questions about his desire to be prime minister, once saying it was as likely as being reincarnated as an olive or finding Elvis on Mars. But it is now almost certain that he will throw his hat into the ring.
Many remain Tory MPs are likely to want to rally around a candidate to stop Johnson. The most likely candidate for this is May, despite her having backed the prime minister’s call for Britain to stay in the EU.
She kept a low profile during the campaign, refusing to campaign for remain with the same force as Cameron and Osborne. This may allow her to pitch herself as a unifying bridge between the Eurosceptic and modernising wings of the party.
She burnished her credentials among Eurosceptics during the campaign by calling for a withdrawal from the European convention on human rights.
Her supporters may also value her reputation for seriousness and as a safe pair of hands in a crisis, which forms a sharp contrast with Johnson’s jovial image.
Throughout the campaign, May managed to keep above the day-to-day fray of the Tory feuding and has experience running one of the great offices of state for the past six years.
Modernisers are pushing Amber Rudd, the energy secretary, who clashed with Johnson during a referendum television debate, to run for the leadership.
George Osborne, the chancellor, has seen his chances of succeeding Cameron effectively destroyed, after he campaigned so forcefully alongside the prime minister.
Among those who campaigned for Brexit, Andrea Leadsom, an energy minister, Liam Fox, the former defence secretary, Priti Patel, the employment minister and Dominic Raab, the justice minister, could all possibly declare bids.
Leadsom is said by some leave campaigners to have been preparing for a leadership bid for many months. In a contest, she would be likely to stress her background in finance to help steer the country through rough economic times or she could potentially try to run on a joint ticket with Johnson in the hope of making chancellor.
Michael Gove, the justice secretary, and friend of both Cameron and Osborne, has always strongly denied he wants the top job but has consistently polled well in surveys of grassroots Conservatives in recent months.
As well as May, there are likely to be other MPs who campaigned for remain who want to put up a fight against Johnson.
Possible candidates from the modernising wing of the party, apart from Rudd, include Stephen Crabb, the work and pensions secretary, and Nicky Morgan, the education secretary, although they are likely to find it very difficult to appeal to a pro-Brexit party membership.
Sources close to Morgan told Sky News she was considering running to carry on Cameron’s legacy.