LONDON, ENGLAND - AUGUST 24:  Andy Burnham speaks to supporters at a Labour leadership campaign rally on August 24, 2015 in London, England. Candidates are continuing to campaign for Labour party leadership with polls continuing to place left-winger Jeremy Corbyn in the lead. Voting is due to begin on the 14th of August with the result being announced on the 12th of September.  (Photo by Carl Court/Getty Images)