Who will be next British Prime Minister after Cameron resigns?
What now for Cameron?
David Cameron has announced there will be a staged exit from Number 10 and a new British Prime Minister by October. The eurosceptics within his party will be victorious and he will go down in history as the Prime Minister who took Britain out of the European Union despite so vociferously campaigning for the exact opposite.
Boris Johnson's fortunes have soared dramatically as the figurehead of Vote Leave.
He has neatly positioned himself to become a main player in any ensuing Conservative leadership challenge. Enter, Prime Minister Boris.
Jeremy Corbyn has also been roundly criticised for not shouting loud enough about why Britain needed to remain an EU member.
With 60 or 70 per cent of Labour members thought to be pro-EU, MPs will pile on the pressure for him to resign too. It may be the moment that many of his opponents have been waiting for.
Who will be the next British Prime Minister?
It does not take much effort to work out who could be the main contenders.
While Michael Gove has previously said it does not interest him, it is not uncommon for politicians to change their minds.
Mr Gove is well-respected and has managed to rise above personal attacks throughout the campaign, but some in the party worry that he is not "normal" enough to win votes across the whole country.
Boris Johnson, the other prominent eurosceptic, has positioned himself neatly as a figurehead for the Brexit campaign. If Britain votes to leave, he will be in prime position to take on the leadership.
Mr Johnson consistently polls well with Conservative members and Mr Gove has enjoyed recent high popularity levels.
But he has made a number of gaffes during the campaign which could have damaged his chances.
George Osborne, the Chancellor, has slipped down the rankings in recent months though, while other Remain campaigners such as Theresa May and Sajid Javid do not perform well either in ConservativeHome polls.
All that could change if Britain confidently votes to Remain and the Brexit campaign falls out of favour with the wider public.
How will it happen?
David Cameron has announced he will resign his post as leader of the Conservative party and Prime Minister.
He has not set out a full timetable but has suggested a new leader will be in post by October this year meaning a leadership contest will be underway in the summer.
The process for electing a new Conservative leader is fairly complex.
Candidates must first be nominated by two sitting Tory MPs via a submission to the chair of the 1922 committee Graham Brady.
If one person is selected they win outright. If only two people are selected by MPs they both go forward to a wider ballot of Conservative party members, conducted by post.
If three or four members of the party are nominated as potential leadership candidates MPs must whittle them down to two choices using a first past the post system with subsequent ballots after fourth place has been knocked out.
Then the two final choices are sent out to the wider party for the postal ballot and Mr Brady will decide the deadline for the vote, before a count begins at noon that day.
The result is then announced to the Parliamentary party and other members.
Here is a run-through of the main contenders
Boris Johnson is considered the most likely Brexit-backer to challenge George Osborne for the leadership, especially if the referendum pans out in favour of the former Mayor of London. Boris Johnson's stance will allow him to ride this wave of Outist feeling in any prospective leadership contest and he is already a well liked politician in the eyes of the public.
His name recognition will put him ahead of other Conservatives who've been more overt in wanting to Leave, and encourage those who've been toying with joining them.
Mr Johnson has recognised this in the past – writing in the Telegraph back in 2001 during a previous leadership contest – that "the Tory party is a vast organism animated by a few vague common principles such as tradition and love of country, and above all by the pursuit and retention of power."
Mr Johnson will thrive if he can persuade Tory MPs that he has this winning appeal.
Ruth Davidson, leader of the Scottish Conservatives, is a clear favourite to lead the Party one day. Although she is not an MP in this country, it's worth watching this space for 2020.
After her success in the Holyrood elections last month, which saw her party come second behind the SNP, she was already tipped as a future successor to Cameron. Ms Davidson has also been praised for her appearances in the EU referendum and for flooring her opponents effortlessly.
At just 37 years old, Ms Davidson – gay and progressive – is seen as the embodiment of a new liberal Toryism. The Telegraph reported that Ms Davidson believes the Scottish Conservatives would have to break away from the UK party under a new name if Boris Johnson becomes Prime Minister. Senior sources close to the Scottish Tory leader said she thinks the former Mayor of London would be toxic to her party’s electoral hopes north of the Border if he succeeds David Cameron.
Once regarded as an obvious candidate to take over from his close friend David Cameron, George Osborne has grown increasingly unpopular among Tory MPs and the grassroots of the Party.
It is now widely accepted the chancellor will be removed from his position in a post referendum reshuffle, as he would need to reestablish himself in a different Cabinet role to have any hope of running for the leadership of the Party in the future.
As many as 65 Conservative MPs rejected George Osborne’s proposed emergency "Brexit budget" earlier this month as "absurd" and criticised his suggestion that he would threaten to "renege on so many manifesto pledges’."
In March Mr Osborne faced a mass Tory rebellion over disability cuts as Conservative rebels went public and claimed they had the numbers required to defeat the government. In the wake of Mr Osborne’s disastrous Budget, the Chancellor admitted that his bid to cut disability benefits had been a “mistake”. But don't underestimate this politician's survival instincts, this politician could easily turn things around.
Theresa May is truly the quiet woman of British politics, but that doesn't mean the "Ice Queen" isn't interested in running for the leadership of the Party.
As a steady Home Secretary, she has kept her head down during the EU referendum debate and could be the perfect person to reconcile the Party in the wake of the dramatic campaign. The Party will inevitably want a Brexiteer as one of their final two candidates to be the next leader, so Ms May could have the best chance - as a sceptical Remainer - of being able to contest them.
In an interview with the BBC this month she gave us a taste of which direction the Party could go under her leadership when she made a clear call for "further reform" to EU free movement rules.
Although she has repeatedly refused to comment on a future bid for the Tory leadership, it's now clear that she, rather than Osborne, might end up being Boris Johnson’s main opponent. Her restrained approach to campaigning for Remain has helped her avoid alienating Tory Brexiteers, and the polls suggest her reputation has held up better than some of her potential leadership rivals.