Jeremy Corbyn has been kicked out and many of his supporters have left the party.

At the same time, he has dismantled the 2019 manifesto, ditching commitments to large-scale nationalisation and public spending to display more fiscal conservatism.

The left of the party, so recently in charge, seems quiet and cowed, while Sir Keir's grip looks stronger than ever, part of a plan to reassure the public things have fundamentally changed.

But has the left really been defeated or are some simply lying dormant? And if they are, could they shape a Labour government?

At the heart of the left is the Socialist Campaign Group, a long-established faction, whose influence soared during the Corbyn years, with figures such as Richard Burgon, Dianne Abbott and John McDonnell as prominent members.

The electoral challenge Sir Keir faces means that this 30-something group of MPs could hold the balance of power in the next Parliament.

Labour needs the swing that Blair achieved in 1997 to win a majority of just one seat. Even the most optimistic of advisers, acknowledging that the polls will certainly narrow, know that a Labour majority, if any, is likely to be below 50.

This would undoubtedly be a huge achievement but could also suddenly leave Sir Keir relying on the SCG to implement his legislative agenda.

We all remember the enormous power the ERG and the DUP were able to wield during Theresa May's premiership.

Some SCG insiders say they are aware of the opportunity and are playing the long game. As one former frontbencher put it when talking about the current leadership: "F**k them, we're going to sit this out."

While they will push for a more radical manifesto behind the scenes they are wary of public showdowns because of the risk of being forced out ahead of the election.

The priority is keeping their seats in order to apply pressure in future and ensure "the party doesn't move even further to the right".

The senior MP also put the number of left-wing rebels much higher than 30, saying around 60 were prepared to defy the leadership in a recent contentious Commons vote banning public bodies from boycotting Israel. In the end though only 10 broke ranks.

"They chose not to stick their heads above the parapet," they explain, "but the numbers were high. And they were even higher recently during the row about child benefit. There were people on all sides asking: if we can't even do this, what is the party for?".

For those supportive of the leadership though, they say potential rebellions are much easier to contain than they were in the early days.

"Back then some bills were giving us serious problems. Now the numbers are negligible."

On whether the SCG could shape Labour in power, he added: "They're not as united as you might think. There are some who are younger and more ambitious. Do they really want to sit on the backbenches for the entire duration of a Labour government?

"I'm thinking of people like Nadia Whittome. They may not be in line for big jobs but surely they will want some sort of role, some sort of opportunity to make a difference."

Another senior staffer describes the group as unfocused and divided: "John McDonnell just does what he wants and most people can't stand Richard Burgon".

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But what about the wider parliamentary party?

One senior Labour MP suggests that the number holding their noses until after the election is much higher, extending well beyond the SCG.

"Keir's support is very broad but very shallow. The project is simply 'to win', the moment we've done that, he'll have no goodwill at all."

They add: "But it all depends on who they feel the pressure from in government...

"At the moment they're very much swayed by the right-wing press but colleagues who have been in government promise me they'll have to listen more to the Parliamentary Labour Party."

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First in the firing line for many will be the tight public spending restrictions, seen as being driven by shadow chancellor Rachel Reeves, enforced by shadow chief secretary to the Treasury Pat McFadden and accepted by Sir Keir as an electoral necessity.

It's a stance that has created resentment, particularly when it appears that the rules are being bent by those at the top.

The senior MP explains: "Rachel just arbitrarily funded a brand new hospital for Hillingdon in the Uxbridge by-election and we still didn't win.

"Meanwhile, colleagues have hospitals with roofs literally falling down and are told by Pat they're not allowed to ask the Tories to fix it as it counts as a spending commitment."

It all paints a picture of a party ahead in the polls, holding its breath and keeping a lid on internal tensions, hoping to get to the finish line.

The last Leader of the Opposition to reach Number 10, David Cameron, appeared, on the surface at least, to hold sway over the Conservative Party, with his modernisation programme.

But behind the scenes, the eurosceptics stood firm, and his time in office is remembered predominantly for Brexit.

Those at the top of Labour have proved that they can get to a winning position and believe they have taken control, but in reality, they may have just bought themselves some time. Beyond that, the real power struggle has only just begun.