A Conservative leadership race is already under way, with a number of MPs publicly declaring that they want to be the next leader or that they are seriously considering running.

Suella Braverman and Steve Baker did not even wait for the news that Boris Johnson was resigning, while others who have long been expected to be frontrunners have yet to openly state they will stand.

A clear runaway favourite has yet to emerge. Here we set out the potential successors, with a rating out of 10 of their chances.

Ben Wallace 6/10

Ben Wallace.

The defence secretary jumped to the fore as the bookies’ favourite, prompted by a YouGov poll that showed he was the first choice among Conservative party members who were asked over the course of Tuesday and Wednesday who they would want to see as the next leader. (Penny Mordaunt and Rishi Sunak were second and third in the poll.)

Wallace has also been at the top of ConservativeHome polls of members’ favourite cabinet ministers on account of his handling of the war in Ukraine and the evacuation from Afghanistan.

Until now he has had a relatively low public profile, but Tory MPs say his popularity may have begun to make him consider a bid, with many regarding him as the type of figure who would mark a stark contrast in style to Johnson.

However, one outstanding question is whether Wallace really wants the job. Speaking to reporters on Thursday before Johnson’s resignation statement, he declined to comment on whether he would run for prime minister, but said the political crisis would not affect Britain’s wartime support for Ukraine.

In contrast, it is known that Mordaunt, Sunak, Sajid Javid and Liz Truss have campaign teams in place.

Rishi Sunak 6/10

Rishi Sunak.

The former chancellor’s leadership hopes were badly dented earlier this year, but he may have re-energised his leadership hopes by his bold move on Tuesday to quit the cabinet, even if Sajid Javid beat him to the button. Sunak was reported on Thursday to have set up a temporary leadership campaign office in a Westminster hotel.

Long regarded as a favourite to replace Johnson, Sunak’s profile took a hit from Partygate – he received a fixed-penalty notice – and from the potentially more damaging controversy over his family’s financial affairs.

That episode sent his popularity plummeting after he had built a strong public profile through his press conferences explaining the Covid support schemes, winning him credit for swift action to keep families and businesses afloat.

However, he has also been criticised recently for slowness to help people in the cost of living crisis and gaffes that suggest he is out of touch. He continues to be viewed by some backbenchers as calm and unflappable, but others believe he may not want the top job as much as some of his inner circle want it for him.

Penny Mordaunt 6/10

Penny Mordaunt.

The former defence secretary rocketed to the fore on Tuesday evening, with bookmaker Coral installing her as the favourite to replace Johnson.

However, amid a torrent of resignations over the past 48 hours, her decision to remain as international trade minister has raised eyebrows. In an apparent move to deflect criticism, Mordaunt broke her silence on Thursday morning to tweet that Wallace was “absolutely correct” when he said that “the public would not forgive us if we left these offices of state empty”.

Mordaunt, a former Royal Navy reservist who became the UK’s first female defence secretary in 2019, had emerged as a firm favourite among the Tory faithful. Results of a poll of party members published at the weekend by ConservativeHome put her as the second choice, just behind Wallace.

Mordaunt had long been tipped for cabinet greatness as a Brexiter – with the reported backing of other Brexiters including Andrea Leadsom – but she was viewed as disloyal under Johnson for backing Jeremy Hunt in the last leadership contest. She has been one of the more forthright ministers when it comes to criticising the PM over Partygate and appears to be setting herself up for a run at the top job.

Sajid Javid 5/10

Sajid Javid.

Despite a lacklustre performance in the 2019 race, in which he failed to make it into the final round, Javid may well have resurrected his hopes by in effect firing the starting gun on a new contest.

He made a dramatic return to the cabinet in June last year as health secretary, after previously quitting as chancellor in a clash with Dominic Cummings.

While he was once talked up by many as a strong contender to leader the party, memories of his relatively short 16-month tenure at No 11 had somewhat faded as decisions taken by Sunak during the pandemic elevated his successor’s profile.

While Javid had the political nerve to jump first with his resignation on Tuesday evening, his letter was also markedly different from that of Sunak, which focused significantly on the need for a different economic strategy. By contrast, Javid’s was more furious in tone, placing a call for integrity at its heart. His statement in the House of Commons on Wednesday was devastating, even if he fluffed some of the strongest lines.

Liz Truss 5/10

Liz Truss.

The foreign secretary was quick out of the traps in declaring her support for Johnson after the departures of Javid and Sunak, but then cut short an official trip to Indonesia.

She was in fourth place – with a considerable gap between her and Wallace – in this week’s YouGov poll of who Tory party members want to see as their new leader.

The move to get behind Johnson was seen as an attempt to shore up potential support from other Johnson loyalists – a not insignificant constituency in any future Tory leadership battle. However, her star has fallen somewhat in recent times as figures such as Mordaunt have edged ahead in some bookies’ estimations.

Nevertheless, Truss remains a frontrunner and has had a campaign team in place for some time. She has been busy burnishing her public profile with Instagram shots and channelling Margaret Thatcher by wearing a headscarf while driving a tank. As the first Tory female foreign secretary, she has taken credit for securing the release of Nazanin Zaghari-Ratcliffe and imposing sanctions on Russian oligarchs, despite accusations the Foreign Office was underprepared for the war in Ukraine.

Tom Tugendhat 5/10

Tom Tugendhat.

The former military officer is a favourite among Tory centrists – itself an obstacle of sorts in a party whose members and backbenchers have shifted right on many issues – and gained ground in terms of the bookies’ odds over the course of Thursday.

Having announced as far back as January that he would stand for leader if Johnson were turfed out, he has been picking up support this week. The former minister Damian Green said he would back Tugendhat in any leadership contest, telling Sky News: “You can take it that Tom is going to run.”

Although it would be highly unusual to have a new prime minister with no cabinet or shadow cabinet experience, some MPs believe it could be good to have a candidate untainted by the Johnson regime.

However, the polyglot chairman of the foreign affairs committee is relatively untested and some worry his focus is too much on foreign affairs and not enough on the domestic agenda to be an attractive option.

Nadhim Zahawi 4/10

Nadhim Zahawi.

The new chancellor has gradually been emerging as an outside candidate who could rely on a compelling personal backstory and a track record of competence in government.

However, his hopes may have been fatally undermined by his decision to take on Sunak’s job as chancellor and then send a letter on Thursday calling on Johnson to go.

The former education secretary impressed his party as vaccines minister, and after being rewarded with a more senior cabinet post, he has done a solid job of neutralising some of the difficult issues facing the Tories on education.

His backstory as a former refugee from Iraq who came to Britain as a child is impressive. But some Tory MPs may worry – as with Sunak – about issues around his wealth, from expenses-era criticism to his former business dealings in oil and gas.

Jeremy Hunt 3/10

Jeremy Hunt.

Despite long enjoying a profile as the bookies’ favourite to replace Johnson, the man who beat him in the last Tory leadership election, the former health secretary’s odds have lengthened. He has frequently been talked about as the “safe pair of hands” replacement for Johnson, but after Javid and Sunak’s resignations, a lack of boldness on Hunt’s part may now be more apparent than ever.

In terms of character, the PM and Hunt are poles apart: Johnson is all bombast and cheap jokes, while Hunt is neither. But his achilles heel continues to be his remainer background.

He came last in a recent Conservative Home vote on who would triumph in a run-off and may lose out to Tugendhat as the centrists’ choice.

Suella Braverman 2/10

Suella Braverman.

After declaring during broadcast interviews on Thursday morning that she wanted to be the next Tory leader, the attorney general was ridiculed by Emily Thornberry during questions in parliament, when her Labour opposite number prompted laughter by saying what an “honour” it was to be facing off with the next prime minister.

Nevertheless, Braverman’s efforts to shore up support before an official contest is already relatively advanced among the party’s 2019 intake. She has also noisily been pressing buttons – in interviews she has regularly declared a supposed “war on wokeness” – selected to appeal to certain sections of the party.

Steve Baker 2/10

Steve Baker.

Braverman’s move to sew up support among hardcore Brexiters may make it difficult for Baker, an eloquent and influential figure on the party’s backbenches who has been telling broadcasters on Thursday that he is “seriously considering” a run.

However, his role during the turmoil surrounding Brexit would make him a particularly polarising figure. Other positions, which would logically lead him to dismantle many of Boris Johnson’s green policies, would mark him out as being more extreme than many other colleagues and indeed the general public.

Priti Patel 2/10

Priti Patel.

In contrast to new frontrunners such as Wallace, the ambitious home secretary has had a team in place for a while. However, while she has enjoyed a following among a hardcore niche of the party – support which itself may be fading, if the latest YouGov poll is anything to go by – she would struggle to gain support among MPs.

Questions of competency – she has been criticised among Tory ranks over her handling of immigration – also hang over her, as do findings in 2020 by the prime minister’s then ethics adviser that Patel broke the code governing ministers’ behaviour, failing to treat civil servants with respect, including by “shouting and swearing” at them.