Andy Burnham outside his house in Warrington, Cheshire. Politicians, as we know, love a metaphor. But do they have to be so literal? No sooner had the Greater Manchester mayor, Andy Burnham , announced that he wanted to run for parliament than … Look! Out he popped from his house on Friday morning in jogging gear, because he’s full of energy and on the right track and hitting the ground running and … oh, do keep up. What is it that persuades a 56-year-old man who is leading every news bulletin in Britain and knows there is a throng of photographers outside to put on some terrible shorts and a 1979-80 Everton strip and expose his paunch and Lancashire tan to the world? Could it be the certain knowledge that by mid afternoon the pictures would be dominating every major news site in the UK – including the Guardian – as feverish discussion continued over whether he could eventually depose Keir Starmer as prime minister? “Burnham off to a running start,” said the Times . Better than a PB.…