Zack Polanski, the new leader of the Green Party of England and Wales, says he wants to replace Labour. That still seems unlikely, but if it were to happen, this is what the early build-up might look like. The party’s membership has more than doubled since Polanski’s election in early September, overtaking the Conservatives, and some polls show them level-pegging with both Labour and the Tories (all far behind Reform). Next May, local elections in London and other big cities could see a realignment in Britain’s political map – a mirror image of Reform’s sweeping gains this year.

