Who will win the race to succeed Theresa May?

Theresa May is widely expected to announce her resignation date on Friday, with 10 June expected to the day that the contest to succeed her will begin.

The prime minister will likely stay in office while the leadership election takes place, with a new leader set to take office before MPs leave Westminster for their summer break in July.

In reality, the race to be the next prime minister has already been underway for months. Candidates have been building campaign teams, giving eyebrow-raising interviews to Sunday newspapers and spending more time in parliament's bars and tea rooms as they seek to win support.

But who are the most likely successors to May – and what are their chances of becoming the next prime minister?

Candidates fall into three main camps: ardent Brexiteers; the new Eurosceptics; and former Remainers.

The Brexiteers

This category is the most crowded by far, with two Eurosceptic former cabinet ministers having already declared their intention to run and an array of current minsters all but certain to do so.

The current bookies’ favourite is Boris Johnson. The former foreign secretary quit the government last summer in protest at May’s Brexit plan, winning him praise from Conservative Brexiteers. A big personality who has clear public appeal, he is seen by some Tory MPs as the party’s best chance of winning a general election. While he has many enemies in the party, with some moderate MPs desperate to stop him becoming leader, his huge popularity with Tory members means he will be considered the strong favourite if he makes the final two.

Johnson’s problem will be securing enough support from MPs to make the members’ ballot, with questions about his competence fuelling support for other Eurosceptic candidates. He will need to work hard to reassure MPs that the errors and gaffes that littered his time as mayor of London and foreign secretary will not continue if he is prime minister. However, his popularity with party members and his growing support among MPs lead some Tories to say he is unstoppable.

Former Brexit secretary Dominic Raab has emerged as another strong candidate from the right of the party. He is reported to have signed up dozens of MPs to support him and has already given several high-profile interviews. Like Johnson, he is a vocal critic of May’s handling of Brexit and would be happy to leave the EU without a deal. Doubts are likely to be raised over his lack of experience – he was in the cabinet for just four months – and suggestions that he lacks warmth and a human touch.

Several current Eurosceptic cabinet ministers are also expected to enter the race. Andrea Leadsom, the leader of the Commons, has said she is “seriously considering” running and is widely expected to do so. She reached the final round in the 2016 leadership contest but dropped out after provoking outrage by appearing to suggest that she would make a better prime minister than May because she has children. Strong performances in the Commons and the media have helped her to rebuild her reputation since.

Penny Mordaunt, the defence secretary, is also an outside bet. She let slip at a recent event that her “campaign team” were frustrated at some things she said, and is tipped to officially launch a campaign when the contest starts. Her recent promotion from international development secretary to defence secretary will also have burnished her credentials.

Michael Gove is another Brexiteer heavyweight who could throw his hat in the ring. The environment secretary is widely respected among Conservative MPs but his standing fell after he was seen to have stabbed Johnson in the back during the 2016 contest, when he initially agreed to back him but then announced his own candidacy.

Like Leadsom and Mordaunt, he has also damaged his standing among the Tory right by staying in the cabinet and backing May’s Brexit deal. Despite this, he is currently the third favourite with bookmakers. If he doesn’t run, his endorsement will be a major boost for whoever he decides to support. Would he make up for his previous actions by backing Johnson, or might he opt instead for Raab?

Esther McVey, the former work and pensions secretary, has already announced her candidacy, while Liz Truss, the chief secretary to the Treasury, has been pitching herself in a series of prominent interviews as a modern Thatcherite and is almost certain to enter the race.

The new Eurosceptics

Home secretary Sajid Javid emerged as an frontrunner early this year but was damaged by rising knife crime and his response to the migrant crisis. As the child of Pakistani immigrants and son of a bus driver, he has a compelling back story, and electing Britain’s first Bame prime minister would be an attractive proposition for many Tories. A former Remainer, he has moved towards the position of Brexiteers and reportedly taken a hardline position in cabinet discussions on how to deal with the EU. His role as home secretary gives him a prominent platform and undoubted experience, but critics accuse him of being robotic.

Vying with Javid to be the main cabinet heavyweight in the race is foreign secretary Jeremy Hunt. Despite being bruised by NHS winter crises and a major row with junior doctors during his time as health secretary, he is generally seen as a safe pair of hands and an experienced minister. He has significantly shifted his position on Brexit, having initially backed the idea of a second referendum but since suggested he would be willing to opt for a no-deal Brexit. Despite his emergence as a passionate Brexiteer, he is unlikely to pick up much support from the Tory right but is said to have won over a significant number of MPs with a pitch as a unifying candidate who is committed to delivering Brexit. His opponents question what he actually stands for and suggest he has similar flaws to May, earning him the nickname “Theresa in trousers”.

Hunt’s successor as health secretary, Matt Hancock, has also emerged as a likely candidate. At 40, he is comparatively young and has only been in the cabinet since 2016, but is seen as a highly competent and loyal minister. He is a supporter of May’s Brexit deal and, despite being a Remainer, expresses a determination to deliver Brexit. He is tipped as a possible future leader but the next contest will probably come too soon for him.

Like Javid and Hunt, he is also likely to struggle in the ballot of party members if the other candidate is an ardent Eurosceptic.

The Remainers

Amber Rudd, the work and pensions secretary, is seen as the One Nation wing of the Tory’s party’s best hope. An impressive performer and likeable figure, she has recovered her reputation since being reappointed to the cabinet, having been badly damaged by the Windrush scandal that forced her to resign as home secretary last year.

However, there are big questions over whether she will run, particularly given that her wafer-thin majority of 346 in her Hastings and Rye constituency means she needs to devote significant time to keeping her seat. Rudd will face pressure from moderate Tories to run but could stand aside and play a “kingmaker” role.

If she decides not to run, other candidates are likely to throw their hat in the ring to represent the left wing of the Conservative Party. They are almost certain to include Rory Stewart, the international development secretary. He has been one of the strongest advocates of Theresa May’s deal but is ultimately a Remainer. A military veteran, he is well-respected but has only been in the cabinet since the beginning of May. Asked about his leadership ambitions in a recent interview, he said he “loves government”, “is really proud of the country” and is “really enthusiastic”.