Is his apparently growing popularity a sign that the Labour Party is returning to its left-wing roots? If the swell in support translates into a win, it would be part of a resurgence in more socialist values in Europe, after years where left-wing parties moved to the center ground. If the electoral success of Syriza in Greece is joined by growing support for Podemos in Spain in elections later this year, it suggests a new appetite for socialism in the European electorate.
Joseph Stiglitz, the Nobel Prize-winning economist, said during a speech in London this week: "I am not surprised at all that there is a demand for a strong anti-austerity movement around increased concern about inequality. The promises of New Labour in the UK and of the Clintonites in the US have been a disappointment."
Corbyn's success may be part of an identity crisis within Labour, which according to polls had been in with a chance of leading a coalition government in May. The party was "smashed to smithereens" by the election results, which saw the Conservatives able to govern by themselves for the first time in nearly two decades, according to Mike Smithson, who runs the Political Betting website.
"The shock of the loss, when many, including me, believed that they were in with a real chance of returning to power, was worse than if the party had been predicted to lose," he told CNBC.