LONDON — To the outside world, Jeremy Corbyn looks doomed. But on the inside, the Labour Party leader's closest aides are digging in for the long haul.

After last week's disastrous by-election defeat to the Conservative Party in Copeland, Corbyn's future was again called into question. For the first time even his closest supporters such as union boss Len McCluskey were showing signs of "peeling away," according to Labour deputy leader Tom Watson.

But in the Labour leader's office, left-wing hardliners have taken complete control. Amid the turmoil of leaks, defeats and resignations that dogged the leader's team throughout February, Corbyn’s most influential officials Seumas Milne and Karie Murphy launched a power grab to take over the party machine, according to aides familiar with the situation. Milne is the party's executive director of strategy and communications; Murphy is executive director of Corbyn's office — a de facto chief of staff.

After Corbyn's well-liked campaigns chief Simon Fletcher abandoned ship earlier this month, Milne and Murphy seized control. Under an internal reorganization, the Labour Party's campaigns, political strategy and communications will be centralized under the pair's command, with an expanded team of officials and MPs reporting directly to Milne, aides familiar with the changes said.

The revamp is designed to "streamline" the leader's office ahead of a radical policy relaunch "within weeks." This is not the first time Corbyn's camp has talked of a relaunch. But officials insist they will soon unveil a platform of populist left-wing policies that they believe will resonate with the public even though such concepts have been considered outside the political mainstream since the 1980s.

“He wants to be prime minister. He believes the world is in flux and this is a moment when he can deliver radical policies that will change Britain for the better in a short period of time” — Corbyn insider

The maneuverings and mindset of Corbyn’s closest aides highlight their undiminished determination to protect his leadership at all costs, dashing hopes of many Labour MPs that he might be prepared to quit. If Corbyn’s aides are to be believed, having briefed POLITICO on condition of anonymity, only an organized plot with significant union and grassroots membership support has any chance of removing him from office.

Corbyn's “core group” of about 20 MPs and officials — now dominated by the Milne-Murphy axis — might be smaller, but it is also tighter, more ideologically committed and as determined as ever to defend their left-wing project, according to conversations with Labour officials who have worked in, or continue to work in, the leader's office. Rumors suggesting otherwise are part of a “false narrative” spun up by Labour dissidents to undermine Corbyn, the leader’s closest aides told POLITICO.

“Everyone is incredibly motivated politically in the core group,” one official close to Corbyn said, determined to bury any notion that they were wavering in their determination to stay on until 2020, the expected date of the next U.K. general election. “We want to put forward a radical policy agenda. We are very passionate about doing that.”

Radical policies

A second official inside Corbyn’s inner circle was more blunt: “He wants to be prime minister. He believes the world is in flux and this is a moment when he can deliver radical policies that will change Britain for the better in a short period of time.”

The official said Corbyn also believed he had a duty to represent the Labour members who voted for him. “Look, he withstood everything that was thrown at him last time [during the leadership election last summer]. The idea he won't now is for the birds. It his chance to enact his vision of socialism — this opportunity won't come around again.”

But Corbyn’s internal opponents believe that even those on the left of the party may ditch him eventually if they conclude that his leadership is harming their electoral chances, one senior Labour Party official hostile to the leadership explained. “I’m working on the assumption that he will be gone next year,” the official said.

Two of Corbyn’s closest allies, the Labour MP Diane Abbott and Unite union chief McCluskey have either unwittingly or wittingly given him deadlines to turn around the party’s disastrous poll ratings. Labour are currently as much as 18 points behind the Conservative Party.

“I’m confident we can close the gap in the coming 12 months,” Abbott told the BBC in December. A month later, McCluskey suggested the Labour leader would step aside in 2019 if the polls had not turned.

Corbyn’s closest advisers insist the party's poll numbers will turn if their policies are given a fair hearing. They blame internal opponents for creating a "false narrative" of chaos and division, which, they say, is stopping them communicating their message to the public.

To get a grip on the message, Corbyn's most senior aides believe they need to root out opposition and centralize control in the leader's office, Labour officials — both supportive and skeptical of the move — told POLITICO. The change is designed to cut out non-Corbynite Labour Party staffers and MPs. Corbyn loyalists accuse the dissidents of leaking of internal polling and focus group results to newspapers which present them as “succession planning" by a leadership preparing to throw in the towel.

Gang of four

The revamp was made easier by the resignation of Fletcher, who fell foul of the increasingly dominant Milne-Murphy axis, according to an ally of the former campaigns chief.

A four-strong “senior management team” which runs Corbyn’s office on a “collective flat structure” has taken on even more power, officials say. The group is led by Milne and Murphy, alongside policy chief Andrew Fisher and the former MP Katy Clark, who manages Corbyn’s relations with MPs. The four Corbyn aides join about 20 MPs who meet every week for an hour on Mondays as the “core group,” away from the rest of their parliamentary colleagues.

Fletcher’s departure has boosted Milne’s position in particular. While Fletcher was part of the top team in his own right, reporting to the Labour Party General Secretary Ian McNicol, his replacement will work under Milne, with campaigns now the responsibility of the leader’s office.

Two new national campaign coordinators, MPs Andrew Gwynne and Ian Lavery, have also been brought into the leadership office under Milne. Their predecessor John Trickett reported to Fletcher.

The Labour leader’s team say they plan to take on and defeat a “false narrative” of crisis that is undermining their ability to get their message across.

Overall, Milne is recruiting three new members of staff to report directly to him — in addition to two who already do so, Matt Zarb-Cousin and James Schneider. The speechwriter David Prescott, the son of former deputy prime minister John Prescott, also reports to Milne, but is shared with Fisher.

The Labour leader’s team say they plan to take on and defeat a “false narrative” of crisis that is undermining their ability to get their message across. They believe an “alternative narrative” is more plausible — that they are under attack from the right of the party, led by Tony Blair and Peter Mandelson, a close associate of the ex-prime minister who served as a minister and European commissioner.

Blair’s big pro-EU speech this month is also eyed suspiciously inside the leader’s office, where officials suspect it was meant to undermine the party’s by-election chances in Stoke-on-Trent Central, which heavily backed Brexit. “The timing of Blair’s intervention was very unhelpful from the point of view of the Stoke by-election,” one aide said. “Blair should’ve realized it would be damaging to the party.”

Labour held onto Stoke but that was overshadowed by the historic defeat in Copeland. Losing a constituency it has dominated for decades was a bad day for Labour, but not bad enough to prompt Corbyn to go. If his closest aides have their way, nothing will.