The sight of Jeremy Corbyn leading the race to become the leader of the Labour Party has caused undoubted panic.
If he were to win then there would be a whirlwind of adverse comments from within the party, and the real chance of people tearing up their membership cards.
If one of the others were to win then the left will still have been invigorated by his showing, especially amongst the local parties.
As a result, the danger for Labour is that it remains inwardly focused. There is an art of being in opposition but also a duty to maintain scrutiny on Government. An inwardly focused party will fail in this duty and the electorate might not forgive them.
Shadow business secretary Chuka Umunna has accused his Labour Party colleagues of "behaving like a petulant child who has been told you can't have the sweeties in the sweet shop". The Streatham MP said Labour should not be "screaming at the electorate" after its poor general election performance.