The Home Secretary is in pole position for the Tory leadership after getting the votes of half the party’s MPs (165) in the first round of the contest on Tuesday, and securing the backing of two rivals.
She is expected to be confirmed on Thursday as one of the two contenders chosen by MPs to go forward in a vote of around 150,000 Conservative members to elect a new leader - and prime minister - on September 9.
In a statement ahead of an MPs’ hustings on Wednesday evening, Mrs May said that Tuesday’s vote showed she was the only candidate able to “unite our party and the country, to negotiate the best possible deal as we leave the EU, and to make Britain work for everyone”.
She insisted: “I have been clear from the start: the party and the country deserve an open, honest, robust debate - and the next leader needs to have won a mandate to lead.
“So there should be no deals, no tactical voting, and no coronation.”
Mrs May’s supporters have dismissed suggestions that some of her backers tactically “lent” their support to Justice Secretary Michael Gove on Tuesday in the hope of keeping energy minister and prominent Brexit campaigner Andrea Leadsom off the ballot paper.
Although the Home Secretary enjoys an unassailable lead among MPs, some supporters fear that her path to the leadership could still be blocked by Eurosceptic activists’ preference for a candidate, like Mrs Leadsom, who actively campaigned for Britain to leave the EU.
Former defence secretary Liam Fox was eliminated from the contest on Tuesday after polling lowest among the five contenders, and offered his backing to Mrs May, saying: “Experience matters.”
Work and Pensions Secretary Stephen Crabb, who quit the race after coming fourth, said Mrs May was the only candidate who could “unite our party and “form a cohesive and strong government”.
Mrs May’s dominant first-round performance and Mrs Leadsom’s strong showing in second place with 66 votes paves the way for an all-woman run-off.
In a move that will put pressure on her rival the Home Secretary published her tax return, meaning that Mrs Leadsom is the only remaining candidate yet to do so.
Her campaign manager, Tim Loughton MP, said it was “not an issue” and said she would publish a summary “as soon as she gets time away from speaking to colleagues and fighting this campaign”.