THEY HAVE TO BE THE OTHER TORY PARTY TO BE VIABLE:

In a sign of the scale of the challenge facing Labour, the modernising candidates used dramatic language to explain the giant steps the party needed to take to win again. Tristram Hunt, the shadow education secretary, said Labour would only win if the party championed aspirational voters who shop at John Lewis and Waitrose. Umunna, the shadow business secretary, who appeared alongside Mandelson on the sofa on the Marr show, said that Labour had been wrong to run a fiscal deficit as Britain entered the downturn in 2008. Kendall, the shadow care minister, called for a "fundamentally different approach" which would see Labour reach out to Conservative voters.

Mandelson, a veteran from the Labour battles of the 1980s, praised Miliband for showing passion but said that the party lost the election after making a "terrible mistake" in discarding New Labour and failing to revitalise it. The former business secretary, who said that Labour faced a challenge on the scale that Neil Kinnock faced in the late 1980s as he moved on after the challenge from the Militant Tendency, warned that the party could not ignore middle income earners.

"Far from embarking on a short-term beauty contest of leaders what we really need is a very, very thorough debate in the party of the sort that was denied us in 2010," he said. "We were sent out and told to say things and to make an argument, if you can call it an argument, that said we are for the poor, we hate the rich - ignoring completely the vast swathes of the population who exist in between."

Mandelson also said Labour must make sure that trade union leaders were not able to abuse the leadership contest as they did in 2010 when they placed large photos of Ed Miliband on ballot papers sent to their members. 

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