One has to wonder if all the GOP retirements aren't an effort to do the same here. Turn Congress back over to the Dims in the hope that GOP leadership will take major hits. And, at the same time, perhaps bring in a whole new crew of Dims who will get rid of Pelosi and Schumer. Makes one wonder. But, back to the UK.
Corbyn’s supporters have slowly gained control of major institutions within the Labour Party. The essential next move is for compulsory re-selection of parliamentary candidates at every election and an organised purge of the Blairites. If the Labour Party does not take that step, I could not in conscience urge anyone to vote for it, even in England, but rather to look very carefully at the actual individual candidates standing and decide who deserves your support.
More explained @ British Democracy Is Dysfunctional