UK: The leadership of the Labour Party has been contentious ever since Ed Milliband snatched it from his brother David and became Leader of the Opposition after Gordon Brown had spectacularly lost the election 2010 following claims Labour overspending had caused the deficit to balloon after the 2008 financial crisis. That claim seemed to provide a rationale to give power to the Conservatives, but not exclusively, going into coalition with the doomed Liberal Democrats. In the following election rout, Ed Milliband lost even more spectacularly as did the Liberal Democrats, giving power to a somewhat surprised Conservative Government. Ed Milliband resigned and now Labour is electing a new leader.
Left-wing outsider Jeremy Corbyn entered the race at the last minute, and against all odds has become the odds-on favourite to win the leadership, touting left-wing ideals such as free education and the cancellation of the nuclear Trident scheme, completely at odds with the other three candidates who seem to be too similar to each other to fight the surge of popularity of Corbynmania.
In the meantime Labour heavyweights have pitched in to criticise the prospect of a Corbyn led Labour party. Tony Blair has twice written articles saying it could finish the Labour party as his policies were not electable.