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Deadline day: Monday June 15, 2015. To claim a place in the Labour leadership election, Jeremy Corbyn needed thirty-five MPs to nominate him by noon. This was the most difficult stage of the contest — it had been designed to be so. The nomination threshold was intended precisely to prevent someone like Corbyn joining the field.

By the end of the previous week Corbyn had secured eighteen backers. A further seventeen MPs would have to submit their signed nomination forms in person to the office of the Parliamentary Labour Party (PLP), nestled in the lower cloister off Westminster Hall. As most were returning to parliament that morning from a weekend in their constituencies, one delayed train could scupper Corbyn’s chances.