What happens when the “most duplicitous, lying electorate that you’ve ever come across” holds an internal contest via secret ballots covered breathlessly by the media with the fate of the country at stake? That description of those currently deciding who might be the next prime minister, from the former Tory leader Iain Duncan Smith, goes some way to explaining why there has been a torrent of blue-on-blue attacks, “dark arts” and betrayal of long-held loyalties over the past week. After MPs managed eventually to oust the prime minister, the relief of being able to select a new leader was only momentary before the infighting began again. “In terms of attacks on candidates, it’s going to be a long, hot summer,” forecast Nadine Dorries, the culture secretary, after an already bruising week of mudslinging. Another cabinet minister reflected: “At first, it was all about choosing a candidate based on their vision, high ideals and philosophy. Over the weekend, that will change as people start unifying instead around who they want to block from becoming PM.” With the leadership election set to conclude on 5 September, only another few days of it will take place behind closed doors in the confines of parliament. It will then spill out across the country, when the two remaining finalists battle it out for Tory members’ support. The journey so far has been dominated by briefing and counter-briefing, as the frontrunners keep one eye on trying to squeeze out supporters from those lagging behind and another on picking off those backing their nearer rivals. Candidates are trying to keep things civil on the surface, but allies and outriders are free to act more independently – usually under the cloak of anonymity. Rishi Sunak has won the most endorsements from MPs, but also attracted significant levels of vitriol. A figure inside one rival camp labelled him a “quisling” because they believed a senior member of the former chancellor’s camp had been spreading lies about their candidate. Dorries, who is backing Liz Truss, accused Sunak’s team of “dark arts” for allegedly trying to engineer getting an easily beatable candidate into the final two with him, and suggested Dominic Cummings was supporting him. A government source said: “For six months, we had to make these huge cost of living decisions and all the while Rishi’s had this filter in his head thinking about how they’ll play in terms of his own leadership prospects – it’s fucking shocking.” Sunak supporters have tried to put on a brave face, one quipping they would follow Michelle Obama’s retort against attacks by Donald Trump: “When they go low, we go high.” Mark Spencer, the Commons leader and one of four former chief whips who are supporting Sunak, said this week he was doing so partly because “there are no skeletons in that cupboard”. Such is the effort to ensure Sunak remains untainted that diehard supporters took it upon themselves to organise chaperoning him around parliament. A WhatsApp group named “the walkers” was set up by MPs to coordinate meeting and ferrying the former chancellor between events, to avoid him being collared by colleagues and journalists. Penny Mordaunt in particular, who surprised many MPs by beating Liz Truss in the first and second rounds of voting – and topping a YouGov poll of party members – has been the victim of particularly vicious briefing. The former Brexit minister David Frost, a Truss supporter, claimed Mordaunt had been a lacklustre deputy and he had asked Johnson to move her; Suella Braverman wasted no time after dropping out of the race in attacking Mordaunt over women’s rights. “The responsible minister, I’m afraid, didn’t stand up for women,” Braverman said, discussing the drafting of a bill on maternity rights for ministers last year, and claiming Mordaunt had not wanted the words “mother” or “woman” to be included. Braverman later threw her weight behind Truss, and is expected to take many of her supporters with her. Asked about the briefing against her on Sky News on Friday, Mordaunt described it as “black ops”, saying: “People obviously are trying to stop me getting into the final because they don’t want to run against me.” She added: “You’ll see from my campaign that I’m not engaging in any of that.” Responding to Frost’s lofty insistence that he would not serve in a Mordaunt government, the backbencher Simon Hoare wrote on Twitter: “Who the hell is an unelected, failed minister to tell any MP what to do? For some unknown reason David Frost perpetually thinks we give a flying xxxx what he thinks. We don’t and we won’t.” It may not rival the drama of Michael Gove stabbing Johnson in the back in 2016, but some loyalties have already been cast aside as the prime minister’s time in office comes to an end. Conor Burns, a minister in the Northern Ireland Office and such a staunch supporter he claimed Johnson had been “ambushed with a cake”, was snubbed for promotion last week to the more senior cabinet position when it was vacated by Brandon Lewis. Mordaunt strongly supported Jeremy Hunt’s 2019 campaign but he refused to endorse her bid and instead rowed in behind Sunak. Sajid Javid was rebuffed by his former wingman the Treasury minister John Glen, who is backing Sunak, while the Treasury chief secretary, Simon Clarke, is supporting Truss. One MP who supported Javid in the previous leadership race said that after he failed to secure a place on the first ballot – having gathered only 12 of the 20 required supporters – Javid approached them with tears in his eyes and entreated to know why they had not done so again. One of the defining elements of such contests is how they make every interested MP a sudden devotee of game theory, plotting out multiple narratives whereby the decline of a rival could assist their chosen favourite, a pastime that reaches a crescendo in the corridor outside the committee room where MPs cast their votes. In the second round, on Thursday lunchtime, an ally of Truss feverishly pitched the idea to waiting journalists that Braverman and Kemi Badenoch were doomed and so should “recognise the reality” and throw their lot in behind Truss, as a unified candidate for the Tory right. Less than a minute later, Braverman, as ever shadowed by her campaign lead, Steve Baker, was busy insisting to the same reporters she was destined for the next round and thus a spot in the upcoming TV debates. Once viewers got a chance to see Braverman’s arguments first-hand, “all bets are off”, Baker predicted. Hours later, the attorney general was knocked out of the race, leaving a final five. As attention turns to the final stages of the parliamentary leg of the leadership election, MPs fear a brutal weekend. Sources on the 1922 Committee, which set the rules for the short contest, admitted it had been deliberately designed to take place from Wednesday to Wednesday, allowing the Sunday newspapers to interrogate and “weed out” awkward policy positions and past behaviour. So concerned are some camps about the dirt that rivals are dishing on them that several are said to have hired media lawyers. Closely watched TV debates will also allow lesser-known candidates such as Mordaunt, Badenoch and Tom Tugendhat to be put through their paces, with each camp suggesting their rivals were likely to struggle under the glare of the spotlight. The stakes will only grow when the candidates are whittled down to two. “There’ll be some grenades being saved for August,” one MP said. “You can’t use up all your ammunition on people just in the knockout rounds.” Despite the humiliating nature of Johnson’s downfall, he is said to still be desperate to regain the popularity he achieved during the heady heights of 2019’s general election campaign. A No 10 source suggested he believed he could “do a Churchill” and make a comeback, swooping in again if the new Tory leader loses the next election and stands down. Another Johnson loyalist said he was “still very angry” and likely to take swipes at Sunak if he emerged as the next leader. But the privileges committee’s call for a mass of evidence on Friday, as it kicks off its investigation into Partygate, was a reminder that he and the wider Conservative party will be dogged by the legacy of his chaotic premiership for some time to come.