Optimism and quiet confidence gave way to jubilation with party’s historic victory in Gorton and Denton byelection

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When the result dropped soon after, it would be obvious this was an historic moment for the Greens; toppling one of Labour’s largest majorities, and claiming their first parliamentary seat north of Herefordshire by winning the Gorton and Denton byelection. But very early on Friday morning, at the count in the Manchester Central Convention Complex, it would be easy to think nothing out of the ordinary was happening.

Green activists and counting agents inside the hall maintained an air of calm, gradually upping their briefings from cautiously optimistic to quietly confident. But there was little sense within the room that this was the start of a seismic shift in British politics.