With less than month to go before London chooses its next Mayor, big promises are being made by the top candidates hoping to take over from Boris Johnson, who has held the post since 2008. Zac Goldsmith is the Conservative party representative from Richmond. A billionaire politician, he is the son of the late financier Sir James Goldsmith. Sadiq Khan, the son of a bus driver is the Labour's candidate for the Mayoral post. Originally from Pakistan, Mr Khan is an MP from South London's Tooting, where he grew up in a council house.