Johnson has mismanaged Covid, Brexit and the economy. Now his inner circle is falling out

Boris Johnson's top political adviser, Dominic Cummings, arrives at Downing Street on Friday.

London (CNN)The UK is deep in its second wave of Covid-19 at the same time as Brexit enters its final act. This might seem enough to keep its leadership occupied.

But the government of Boris Johnson is now engulfed in a political power struggle that is very publicly playing out on the newspaper front pages -- and could, some Conservatives hope, signal a shift in influence on the Prime Minister.
Late on Wednesday, Johnson's director of communications, Lee Cain, resigned from his post. Two days later, it appears that the Prime Minister's chief adviser Dominic Cummings -- a divisive figure often painted as the mastermind behind the Brexit campaign and Johnson's premiership -- may be gone by Christmas.
The political storm surrounding Johnson and his team of advisers first broke on the same day that the UK's coronavirus death toll passed the eyewatering 50,000 figure.
    Johnson's political advisers briefed Westminster journalists Wednesday evening that Cain, one of the PM's closest political allies, had resigned from his job. Downing Street had spent the day fielding complaints from Conservative lawmakers who were alarmed at news reports suggesting that Cain was set to be promoted to Johnson's chief of staff.
    UK media reports also cited sources suggesting that Johnson's fiancee, former Conservative director of communications Carrie Symonds, was opposed to Cain's promotion.
    Conservative MPs believe that the story was leaked as part of a power grab by Cummings in order to pressure the PM into giving Cain the job.
    "It seems clear to me that they tried to bounce Boris into making Cain his chief of staff by leaking it to the media. But none of us wanted that and we are sick of not being listened to," a former cabinet minister told CNN. "We have had enough Cummings, Cain and the damage they are doing to our party. So yesterday we made sure Boris understood that via the chief whip."
    Lee Cain arrives at the back of Downing Street after announcing his resignation from the UK government.
    That backlash appeared to have the desired effect and, after meeting with the Prime Minister, Cain resigned, saying he would leave his post at the end of the year.
    After news broke of Cain's departure, rumors began circulating that Cummings was threatening to resign himself.
    Cummings told the BBC that "rumours of me threatening to resign are invented," though added that his "position hasn't changed since my January blog."
    The blog post to which he is referring stated that Downing Street was aiming to "improve performance and make me much less important -- and within a year largely redundant." This, sources familiar with the matter explained to CNN, meant it was very likely that Cummings would be gone by Christmas.
    Transport Minister Grant Shapps further fueled the case for Cummings' departure in comments to Sky News in London on Friday.
    "As he wrote right at the beginning of the year in his own words, he planned to make himself largely redundant this year, with the big thing that he'd worked on, of course, which was Brexit coming to an end at the end of the transition period which is December 31," Shapps said of Cummings. "The other big thing has been helping to ensure access to mass testing and these two things are on the horizon now."
    Speaking to Reuters news agency, Shapps said "advisers come and go over a period of time" and stressed that ministers take the decisions, but acknowledged that Cummings' had been influential in his role.
    "He was always someone who would sort of shake things up, he didn't take things just because they've been done that way, that they couldn't be done any other way," said Shapps. "And it's always good, I think, to have people who challenge the system and challenge the way things are done. He's obviously been very influential in that way."
    Dominic Cummings, left, and Lee Cain, right, attend a press conference by Boris Johnson in December 2019 in Watford, England.
    Both Cummings and Cain and Cummings were key members of the Vote Leave team which followed Johnson into Downing Street in 2019, having successfully campaigned for UK voters to reject EU membership in the 2016 Brexit referendum.
    "It has been a privilege to work as an adviser for Mr Johnson for the last three years -- being part of a team that helped him win the Tory leadership contest, secure the largest Conservative majority for three decades -- and it was an honour to be asked to serve as the Prime Minister's Chief of Staff," Cain said in a statement following his resignation.
    Johnson said he wanted to "thank Lee for his extraordinary service to the government over the last four years. He has been a true ally and friend."

    Bitter factionalism

    So, what happened to these close friends? There had been speculation that Cain was upset by Johnson's decision to hire a new press secretary, Allegra Stratton, to front the soon-to-start daily Downing Street briefings. Stratton is not only a high-profile former journalist, but most recently worked as an adviser to Rishi Sunak, Johnson's finance minister.
    Downing Street sources told CNN that while Cain was in favor of hiring Stratton, his real gripe was that he wanted her to report to him. She will instead report directly to Johnson, effectively sidelining the director of communications.