Jeremy Corbyn during the 2016 leadership debates. Photo: PA

“He’s taking us back to 1983!” That was the accusation levelled at Corbyn from the moment he was elected Labour leader in 2015. Neil Kinnock, who himself spent much of the 1980s dragging Labour back to the centre ground, put this point to me in no uncertain terms last year. The theory was that with Corbyn at the helm, Labour would once again lurch to the left, suffering the inevitable electoral consequences.

The first part of this conventional wisdom proved true: when the election was called, Labour unveiled a radical left-wing manifesto. The second part has proved completely, utterly wrong. Michael Foot’s Labour Party lost 52 seats; Corbyn’s, quite remarkably, has gained 29. That includes the people’s republic of Kensington, once one of the Tories’ safest seats.

We should not get carried away. Labour was still beaten well into second place. Corbyn’s supporters will point to his extremely high vote share—at 40 per cent, it is an increase of 10 per cent on 2015—but the Conservatives have won by far the most seats.

Still, Corbyn will take heart from the result. Crucially, he and his supporters will now feel the leadership is his for the long-run. With the prospect of another general election soon, and with dozens of new MPs elected for the first time thanks to the Corbyn swing, therefore owing their allegiances to him, he will expect to hang on. His critics set him the test of winning MPs—he has done just that.

And Corbyn triumphed in the most difficult of circumstances. A senior Labour source told me shortly after he was re-elected Labour leader last year: “honestly, this is a universal lesson of politics: divided parties don’t win elections.” Corbyn hasn’t won—but for him to make gains at all when so many of his MPs were briefing against him is nothing short of remarkable.

Will it be enough to convince the critics in his own party? We should not rule out the chance of another leadership content—and the ensuing bloodbath—entirely. Crucially, a hefty part of Labour’s moderate wing didn’t just oppose Corbyn during the campaign for his perceived unelectability; they actually disagreed with his ideas and policies. It is difficult to see last night’s result doing much to placate his most vehement critics.  

But if any leadership challenger—Chuka Umunna, Stephen Kinnock and Clive Lewis were all mentioned during the campaign—were to stand, it is difficult to see how they could topple Corbyn. Even if they received the required nominations from the party, the membership would likely prove an impassable obstacle. 

The political landscape is littered with the corpses of those who underestimated the members’ allegiance to Corbyn. Now that he has led Labour to a better-than-expected result, this loyalty will only harden. 

So Corbyn’s allies will now feel they have a mandate to remake the party. The much touted “McDonnell Amendment,” which would lower the threshold for MPs’ nominations in leadership contests, is very much on the cards. Currently, 15 per cent of Labour’s MPs must nominate a leadership candidate if he or she is to make it onto the ballot paper. This amendment would change it to 5 per cent.  

If this happens, a hard left presence would be ensured on the ballot paper in future leadership elections. Then, Corbyn’s triumph will go beyond the result last night. His long-term political project will have taken an almighty step forward, too.