Voting has formally opened to choose the next Conservative leader, and Theresa May’s successor as prime minister, with Boris Johnson the clear favourite and four of the 10 candidates at risk of being eliminated in the first round of voting.
The 313 Conservative MPs will be able to cast a single vote from 10am until midday with a result expected at around 1pm on Thursday. Successive rounds of MP voting will whittle down the candidates to a final two, who will be put to a vote of Tory members.
Under revised rules to the contest, introduced because of the large field, to reach the next round of votes on Tuesday, candidates must secure at least 17 votes – themselves and 16 others – with several of them looking unlikely to do this.
According to tallies of public declarations by MPs, the health secretary, Matt Hancock, has just passed the threshold, but four other hopefuls are struggling: the former chief whip Mark Harper, who has eight public backers; the international development secretary, Rory Stewart, with seven; the ex-work and pensions secretary Esther McVey, on six; and the former Commons leader Andrea Leadsom, on four.
Much could change in the voting, which is secret, given that more than 70 Conservative MPs have yet to declare their allegiance, but it would be a significant surprise if Johnson did not top the vote.
In fact, it is possible that the former foreign secretary, who emerged from his recent media seclusion to formally launch his leadership campaign on Wednesday, could even reach the 105 MPs’ votes needed to automatically be put in the run-off vote of members.
If several candidates are removed in the first round of voting, the battle will be on for the other hopefuls to gain their backers.
Under the rules, even if all 10 candidates get at least 17 votes, the candidate with the lowest number will be eliminated. In the next round on Thursday, the threshold to progress will be 33 votes, and again the lowest scorer will be gone if all achieve this.
If needed, there will be further rounds of voting on Wednesday and Thursday next week, this time with no threshold, and with the candidate with the lowest number of votes eliminated each time.
The final two will then participate in hustings and various TV events. The winner will be announced on 22 July.
The race was sparked by May’s decision last month to stand down after successive failures to get her Brexit deal passed by parliament. She formally made the step on Friday, thus setting the contest in motion.