Labour's traditional working class supporters are abandoning the party in their droves. But can Labour win them back without alienating the middle-class voters it needs to win the next election? David Goodhart explores the tensions between two traditions in the Labour movement - a liberal wing focussed on equality and diversity and a conservative strand that is more concerned with issues of solidarity and community. And he examines the new Blue Labour school of thought, which believes that the best way to unite the two traditions is to rethink the Big State approach that became a defining element of the post-war Labour Party's identity.