BY THE third week of May 2015 a sense of ferment began to overtake those on the Labour left who thought it was essential to stand a candidate for leader but who had so far failed to find one.

The clock was ticking down to the deadline of June 15, by which time any candidate would need to gather the nominations of 35 MPs to go forward into the race.

Behind the scenes, frantic calls flew back and forth. “We started thinking about almost anyone,” recalls Jon Lansman, a lynchpin of the Labour left. “We felt you couldn’t really have anyone who was new but we thought about Keir Starmer [a new MP but former director of public prosecutions]. We even thought about Angela Eagle at one point — could we back Angela? Would she stand? I made a call. I urged her to stand on the basis that she’d be better than the others. With hindsight that was probably not so. We were desperate.”

Activists had no such qualms about the new arrivals to Parliament and were pestering them to run. Michelle Ryan was among many Labour members in communication with the well networked MP Clive Lewis, who had developed an instant rapport with the grassroots.

“I actually asked him to stand,” she says. “I sent him a message and said: ‘Can you stand for Labour leader?’ And he said, ‘I don’t even know where the toilets are.’”

Meanwhile, John McDonnell — who was opposed to standing a candidate as he thought there was no hope of getting the nominations — was penning an utterly bleak article for Labour Briefing, a journal published by the Labour Representation Committee (LRC), an organisation of the left.

“This is the darkest hour that socialists in Britain have faced since the Attlee government fell in 1951,” it began.

“Everybody was tearing their hair out, there was despair,” recalls activist Michael Calderbank. “The situation was so desperate people were thinking ‘Why am I in this party anyway? Not only has it just fucked up and failed to challenge Cameron but it’s likely to compound that by drawing the wrong lessons.’”

A wacky idea now took shape within the Campaign for Labour Party Democracy (CLPD), Lansman’s main organisation. “Could we find someone who would be a caretaker leader, who would do it in order to have a debate about the future direction of the party and then have another leadership election two years later?” Lansman recalls. “It was in that context that we began to think about people like Jeremy.”

Remarkably, Lansman says that until this point the idea of Corbyn running for leader “never entered my head.” “We suffered from a blindness to anything other than a conventionally acceptable candidate. I thought John McDonnell was credible, Michael Meacher was, Jon Trickett was for conventional reasons.”

But none of them was willing to stand.

On May 26, Lansman attended a drinks reception for new Labour MPs hosted by Tulo, the Labour-union liaison organisation. There he spoke to Tulo’s national officer, Byron Taylor. Lansman, who had adopted an optimistic attitude despite everything, approached Taylor and said: “I think we can get 35 nominations but the question is, who’s the candidate?”

Lansman ran through the list of names and the obstacles to each of them standing. When he finished, Taylor’s answer was instant and unequivocal. “It’s got to be Jeremy,” he said. “Jeremy? Really, Byron? Why?” Lansman replied, taken aback at Taylor’s certainty. “Look, he’s got all the right policies,” explained Taylor. “People will vote for Jeremy. They like him. They respect him. Jeremy’s the nicest man in politics. He hasn’t got any enemies.”

The last line immediately struck Lansman. “I’d never thought of it like that,” he remembers. “I’d never thought of looking for a candidate without enemies... That really sold me on the idea. That was when I started really arguing for Jeremy.”

The following day, May 27, saw the first of two fateful meetings of the Socialist Campaign Group, the body that would ultimately decide whether to stand a left candidate or not.

The MPs who gathered in Westminster debated if it would be wise. “There were some who thought that we’ll be humiliated, that we’ll look weak,” says Clive Lewis, “and I remember saying: ‘If we don’t stand anyone we’ll look even weaker.’”

They discussed the alternative of backing one of the existing candidates in return for concessions but there was no agreement. Overshadowing it all was the problem that, if they did wish to run a candidate, they still had no volunteer.

And then, tentatively, Corbyn raised a suggestion: “What about if I stand?” As an integral member of the Labour left, Corbyn had been right in the middle of the agonising search for a candidate all along. As early as May 12 he had said it was “essential that there is a left anti-austerity candidate in the leadership election,” even as he shared McDonnell’s scepticism about the numbers. Virtually all of the organised groups on the Labour left had come to the same view. Thousands were signing a petition calling for an anti-austerity contender. Here was a problem that Corbyn could solve.

On May 27 it seemed like a relatively small sacrifice to make. Despite Lansman’s optimism, the chance of a left candidate being nominated by 35 MPs looked as slim as McDonnell insisted it was.

When Corbyn offered to stand he was volunteering, in all probability, for no more than a couple of weeks of lobbying and media appearances, a chance to raise the issue of austerity and, when he failed to make the ballot, to demonstrate that the leadership election rules were rigged against the left.

Nevertheless, the silence that greeted Corbyn’s offer at the Campaign Group suggested that not everyone thought it was a good idea.

Another meeting was scheduled for the following week. In the interim, discussion raged within a small group at the heart of the Labour left over the merits of a Corbyn candidacy. “Basically Jeremy began to gather various people lobbying for him,” says Lansman, “mainly CLPD people and Byron [Taylor].” But the man himself was still weighing it up.

On the eve of the all-important June 3 Campaign Group meeting he met an ally, later to take up a senior position in his campaign, who recalls: “We were sitting on the terrace at the House of Commons. We were talking with John [McDonnell] and Jeremy and a few other people. John was still quite anti-standing a candidate at all. John was talking to somebody else for a moment and Jeremy said: ‘John doesn’t want to do it, Diane doesn’t want to do it again, do you think I should?’ I said ‘Yeah, I think you should.’”

As they spoke, the ally got the impression that Corbyn was quite keen on the idea. “He had no expectation of getting on the ballot paper but I think he, like me and everyone else, was just despairing at the state of the debate within the party and wanted it to change.”

With Abbott and McDonnell out of the picture “he knew it fell to him” to change it.

When the Socialist Campaign Group met in room W1 off Westminster Hall in the Houses of Parliament on June 3, there were no journalists outside with their ears to the door. There were no camera crews on standby, no breaking news alerts and there was no Guardian live blog. No voices from the right of the party were issuing dark warnings of impending doom. Simon Danczuk was not yet aware that he should be angry.

In fact, there was virtually no anticipation at all — not even from those on the Labour left, most of whom, other than the people in the room, were unaware that the meeting was taking place.

Cat Smith, the young MP, arrived at the meeting confident that her friend would run “after much nagging from me and others.” Jon Lansman went into the room “really quite determined” that Corbyn should stand and, unbeknown to Corbyn himself, had been busy persuading people to attend the meeting in order to back him. Michael Meacher, for one, was “completely on board.”

The attendees, who also included John McDonnell, Diane Abbott, Kelvin Hopkins and Clive Lewis, were well aware of the strong pressure they were under from activists to put forward a candidate. They discussed the pros and cons of running but the issue had largely been settled. The prevailing view was that there must be a left presence.

McDonnell, who chaired the meeting, repeated that he would not stand. “I’ve done it enough times, I’m not doing it again,” he said.

Abbott echoed the sentiment, saying that she had a run in 2010 and did not fancy it this time round. McDonnell turned to Corbyn, who was sitting at the end of the table, and said flatly: “It’s your turn.”

Suddenly the whole room was looking at Corbyn. “All right,” he said to his colleagues. “I’ll stand if I’ve got your support.” “OK, if you’re going to do it, we’ll back you,” came the reply.

Corbyn was a leadership candidate.

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