In 2017, Jeremy Corbyn had just a handful of allies in the parliamentary party; he started his general election campaign more than 20 points behind the Tories; his own party’s central office was staffed by his internal opponents; and he controlled few, if any, of the levers of power within the Labour Party.
Yet he oversaw the party’s first election gains since 1997 and the biggest increase in its vote share since 1945, and he deprived Theresa May of her parliamentary majority. Meanwhile, the Corbynite ranks in parliament were boosted by the addition of charismatic younger politicians such as Dan Carden and Laura Pidcock.