Tears and tantrums mark London mayor race The incumbent has exploded with fury in a foul-mouthed tirade at the "barefaced liar" running against him and the leading challenger has burst into tears while watching his own campaign broadcast. The contest for London mayor is once again ripping up the conventions of British politics. Two of the UK's most recognisable politicians - the blond tousle-haired mayor, Boris Johnson, and Ken Livingstone, a leftwing veteran of London politics - are locked in combat for control of the city's top job. The prize that beckons for the victor of the May 3 election is the biggest personal mandate in Britain and the kudos of welcoming the world to the capital at this summer's Olympic Games. Mr Johnson, a columnist for The Daily Telegraph newspaper and a former Conservative member of parliament, is known for his florid rhetoric, sharp wit and tendency to eccentricity - factors that have seen him consistently polling ahead of his party among voters. In 2008 Mr Johnson unseated Mr Livingstone as mayor, a post the latter had held - and shaped - since its creation at the turn of the millennium. Mr Livingstone's return to the fray as the Labour party candidate, along with Brian Paddick, a former senior police officer standing again for the Liberal Democrats, has prompted some to complain that this "groundhog day" line-up would produce little more than a rerun of stale arguments. But while the leading dramatis personae are the same, the political backdrop has been transformed. Labour's 13 years in power, first under Tony Blair and then Gordon Brown, came to a dramatic end in 2010 when the Conservatives and Liberal Democrats, the third party, agreed to form Britain's first coalition government since the second world war. Mr Johnson was a contemporary of the British prime minister, David Cameron, at both Eton, Britain's most elite private school, and Oxford university. All these things become campaign issues in a year when government austerity measures are dominating the national debate. The Labour candidate has sought to exploit his opponent's political pedigree, painting Mr Johnson as a "true-blue Tory" concerned only with the interests of the wealthy. His flagship pledge offers lower-income Londoners a measure of relief from their financial strains, reversing three years of transport price rises under Mr Johnson with a 7 per cent cut in Tube fares from October 2012 and a freeze on fares in 2013. Mr Johnson argues that no one is better placed than he to make the capital's case for critical spending and allies boast he remains "just a text away" from the prime minister and George Osborne, the finance minister. He frequently cites hard won agreements over funding for key infrastructure projects such as Crossrail, a £16bn rail route linking east and west London, and upgrades to the London Underground rail network. But Mr Livingstone's return to campaigning has been marred by a row over his tax affairs and his "fare deal" has come under a concerted attack from Mr Johnson, who says it will wreck planned investment in London's transport infrastructure. The Labour campaign message was also blown off course this month, when Mr Livingstone, watching the unveiling of his own political broadcast, began to weep at the sight of Londoners saying: "Win it for London, Ken." Though the participants were ordinary citizens the film was scripted, prompting claims of "crocodile tears" from his detractors. Voters" reactions to all of this are proving hard to read. While Mr Johnson has led Mr Livingstone by a margin of between 6 and 8 percentage points in several polls, two others have put him a mere two percentage points ahead - within the margin of error of such surveys. But the Conservative incumbent retains a remarkable level of support from a segment of London Labour voters who ought to be his natural opponents. Peter Kellner, president of the pollsters YouGov, ascribes this to Mr Johnson's idiosyncratic appeal. "Most of them think Boris has done well as mayor and regard him as charismatic, even though they feel he is on the side of the rich," he said. The leading candidates in the race to be the next London mayor have published rafts of policies on core themes of transport, crime and housing, writes James Pickford. Yet much of the campaign coverage has focused on a row over tax avoidance. Ken Livingstone, the Labour party candidate, came under pressure in February after it was reported that he had channelled his earnings from media appearances and public speaking engagements through a private company, making him liable to pay corporate tax at 20 per cent, rather than a higher rate made up of income tax and national insurance. While the arrangement is legal, Mr Livingstone opened himself to charges of hypocrisy in light of his strident attacks on "tax avoiders." Mr Livingstone defended his position during a live radio debate with other candidates by suggesting Boris Johnson, the Conservative mayor seeking re-election, had adopted a similar arrangement - prompting an expletive-laden rebuttal from Mr Johnson as the candidates travelled together in a lift after the show. When the resulting media din drowned out their attempts to debate policies, the four candidates agreed to resolve the issue by publishing their taxes and earnings from the past four years. While common in the US, this momentous decision broke a long-held taboo among British politicians over making such information public. The response was swift. David Cameron said this month that it was "increasingly likely" he would become the first British prime minister to publish his annual tax statement, and other ministers are now considering whether to follow suit. Neither Mr Johnson nor Mr Livingstone are making any predictions. "It's neck and neck over Beecher's Brook," says Mr Johnson, referring to a fence in the Grand National, Britain's most watched horse race. No one should take the London electorate for granted.