Two of the foreign secretary’s top backers have branded her main rival Penny Mordant unfit for prime minister as the contest turned ugly – undermining her claim to be running a clean campaign. The Tory infighting comes as a senior Truss backer revealed frustration with MPs who failed to vote for her as promised, telling the Independent: “This is the most duplicitous lying electorate you’ve ever met.” David Frost accused Ms Mordant of failing to “master detail” when she was his deputy as Brexit secretary. The attacks were condemned by David Davis, the former cabinet minister and Mordaunt supporter, as the “watch” response to his candidate grew. “Someone catches up and appears to be the real challenger and then the black-ops start,” Mr Davis told Sky News shortly after Ms Mordaunt narrowed Rishi Sunak’s lead. Instead, Ms Truss is in third place with just 64 votes – behind 101 for Mr Sunak and 83 for Ms Mordant – ahead of a weekend of live TV debates. However, the secretary of state’s campaign was boosted on Thursday night by the support of Suella Braverman, who was kicked out of the contest in the second ballot earlier in the day. Earlier, Ms Truss raised eyebrows by promising a new budget “on day one” of taking office, an event that would take weeks of preparation, while failing to deliver on her promise of a new economic plan. Her campaign has stuttered despite a shift to the right with a wavering withdrawal from the European Court of Human Rights and a pledge to scrap green levies on fuel bills. Another Truss ally admitted that the next round on Monday would be “absolutely critical” as he brought in Ms Braverman, the relegated candidate, to try to secure most of her 27 votes. The Secretary of State’s spokesman praised the defeated candidate, saying: “Suella Braverman has run a campaign of which she can be rightly proud. [of].” Sources later confirmed to The Independent that Ms Braverman would vote for Secretary of State in the next vote. Steve Baker, who supported Ms Braverman before she was expelled, said he would follow her lead. But Ms. Truss will need almost all of Ms. Braverman’s 27 votes to close the gap with Ms. Mordant, whose support increased the most, by 16 votes, on the second ballot. The former defense secretary also secured the coup of approval from Tobias Ellwood, the chairman of the Commons defense committee and a former Remainer leader. Mr Ellwood suggested Ms Mordaunt was able to match the 32 votes won by Tom Tugendhat – the candidate most likely to be knocked out on Monday’s third ballot. He pointed to their common stance on defense matters, saying: “I see the possibility of many of them migrating [to Ms Mordaunt] and I invite Tom Tugendhat himself to support Penny.” The first stage of the contest will not be completed until next Wednesday – unless someone drops out – after which Tory party members will choose between the two surviving candidates. A bombshell poll on Wednesday gave Ms Mordaunt a huge lead among the grassroots – who appear to favor a clean break with cabinet ministers tarnished by Boris Johnson’s reign. Mr Sunak’s camp said it was “pleased” with his 101 votes and his rivals were changing their positions, a source said: “Some of the other candidates are now starting to back away from what they said before.” The former chancellor would not take part in “these funny games that some have suggested”, the source insisted – amid suggestions that votes could be “loaned” to Ms Truss, to knock out Ms Mordant. This seems highly unlikely anyway, given that Mr Sunak would have hoped to have secured many more than 101 supporters by this stage. Kemi Badenoch remains Ms Truss’s challenger to be the party’s far-right candidate, with 49 votes – while centrist Mr Tugendhat slipped, on 37 votes. Earlier Lord Frost, who will back Ms Truss in the coming days, criticized Ms Mordant’s abilities, saying he was “very surprised at where she is in this leadership race”. “I felt that he did not know the detail that was necessary in the negotiations last year. It would not always give tough messages to the European Union when it was necessary,” he warned. Following the results of the vote, Simon Clarke, chief secretary to the Treasury, said: “David Frost is a very senior figure in the Conservative Party. He has worked very closely with all the major players in this fight. He has made his views known and I think that is an important factor.” At her launch event, Ms Truss put herself on the spot about her team’s aggressive briefing, promising not to make “derogatory comments” about her opponents. Defending her decision not to resign over the Chris Pincher scandal, as other cabinet members quit, she said: “I’m a loyal person, I’m loyal to Boris Johnson.” But General Lord Richard Dunnatt, the former head of the army, described the launch as “dignified”, telling GB News it was “tainted by Boris Johnson’s legacy” because of her failure to resign. Ms Braverman also criticized Ms Mordaunt for introducing gender-neutral language into the draft maternity bill, which originally referred to a pregnant woman rather than a pregnant woman. “The relevant minister did not stand up for women and in fact did not reflect the views of many in our party about the desire for women to be authentically represented on the face of the bill and in the legislation,” she told Sky News. Ms Mordaunt denied the charge, insisting she changed the bill “to use female terms” after it was drafted by someone else. Speaking on LBC, Sir Keir Starmer said he did not “care” which person wins the contest to replace Boris Johnson in No 10 and challenged them to go to the country for an election. Pressing his views on Ms Mordaunt, the former Tory defense secretary who has quickly become a front-runner in the contest, the Labor leader insisted: “I don’t mind who I’m up against.” “We are ready. Whoever wants to call an election, whoever the candidate is, let’s do it. Please do it so that we can take our positive case to the country and bring about the positive change that we really want.”