Red Ken's fourth bid for City Hall officially begins today, as he launches his long-anticipated campaign to become the Labour candidate in the 2012 Mayoral elections. His only competition so far comes from former MP Oona King (although Guardian blogger Dave Hill is scrunching up his face and desperately wishing into existence an unlikely bid by Peter Mandelson). Candidates must declare themselves by 18 June, with decision time arriving on 22 September. Then the real fun begins.
