Four candidates will be on the ballot paper when Labour Party members get to vote on Ed Miliband’s successor in September. Nominations closed on Wednesday and Shadow Secretary of State for Health Andy Burnham is the bookies’ favourite. Burnham received 68 nominations from MPs (the minimum to be on the ballot was 35), Yvette Cooper achieved 59, Jeremy Corbyn 36 and Liz Kendall 41, with 25 MPs – including Ed Miliband and deputy leader Harriet Harman – deciding not to vote.

The veteran Labour MP Jeremy Corbyn is the most left-wing of the candidates, while Andy Burnham and the Shadow Home Secretary Yvette Cooper are seen more as continuation candidates, struggling to distance themselves from one another in a fight for the top job in the centre-left party.

Chuka Umunna – the Shadow Business secretary who put himself as a leadership candidate early on and was reportedly backed by the former PM Tony Blair – withdrew his leadership bid and publicly backed Liz Kendall. Kendall is seen as the moderniser – subscribing to the “Third Way” centrist approach that tries to reconcile right and left-wing politics on a populist platform. It has served party leaders well in the past, including Blair and the former US President Bill Clinton.

Mary Creagh was unable to secure the support she needed and dropped out without nominating any of the other candidates.

Labour’s deputy leadership shortlist has also been finalised: Tom Watson, Caroline Flint, Ben Bradshaw, Stella Creasy and Angela Eagle will compete to replace Harriet Harman.

Following the poor performance of the Liberal Democrats in the general election last May, Nick Clegg stepped down as leader.

Now only eight Lib Dem MPs remain in the House of Commons – two of which are standing to succeed Clegg.

Norman Lamb has been MP for North Norfolk since 2001 and was Minister of State for Care and Support for three years in the coalition. Lamb is considered more of the continuity leader than his opponent.

The second candidate, former President of the Liberal Democrats and MP for Westmorland and Lonsdale is Tim Farron, who seems almost certain to win the leadership bid, given his track record of winning big in his elections and the fact that he is not ‘tainted’ by involvement in the Conservative-Liberal Democrat coalition government. Tim Farron has gained strong support from prominent members of the party and is seen as more left-wing than Nick Clegg, making any possibile future colaition proposals with the Conservatives far less likely.

Farron voted very strongly against increasing the cap on undergraduate tuition fees from £3,000 to £9,000, and voted in favour of allowing marriage between two people of same sex at the second reading of the Marriage (Same Sex Couples) Bill.

However, he did not vote for equal marriage on the third reading of the Bill, which he put down to his religious upbringing. Unlike Clegg, who is an agnostic, Farron is a church-going Anglican.

2016 Mayor of London candidates incumbent Mayor Boris Johnson has chosen not to run for re-election for a third term in office as he is instead now the Conservative Party Member of Parliament for Uxbridge and South Ruislip. He has announced his intention to remain Mayor until his term ends in May 2016.

Several party members have announced their candidacy for the Conservative and Labour parties, with just one official candidate for the Liberal Democrats: the leader of the party in the London Assembly, Caroline Pidgeon.

And the controversial broadcaster, writer and former MP for Bradford West George Galloway has thrown his hat in the ring as the Respect Party candidate.

However, with the Richmond MP Zac Goldsmith formally announcing his candidacy for the Conservative Party’s bid for Mayor of London, the media have been buzzing and Goldsmith – an Old Etonian who got kicked out for smoking cannabis and is the former editor of the Ecologist – is considered the strongest option for the Tories.

Other Conservative candidates include the British businessman and the first and current Deputy Mayor for Policing and Crime in London Stephen Greenhalgh, and the former footballer Sol Campbell.

Labour’s candidates are almost all current London MPs, but the former Olympics Minister and MP for Dulwich and West Norwood Dame Tessa Jowell is presently deemed the frontrunner. The former Shadow Minister for Public Health and current MP for Hackney North and Stoke Newington Diane Abbott and former Universities Minsiter and MP for Tottenham David Lammy have put their names on the ballot sheet, with Tooting MP Sadiq Khan also proving popular with Londoners.

People have already started speculating as to whom will succeed David Cameron as leader of the Conservative Party after Prime Minister David Cameron said he would step down before the 2020 election.

Four MPs are in contention – three of which are currently in cabinet. George Osborne, current Chancellor of the Exchequer and First Secretary of State (making him the de facto Deputy Prime Minster), has solid support from the party and is seen as Cameron’s natural successor.

The Secretary of State for Business, Innovation and Skills Sajid Javid is also in contention, with growing support from party activists.

The Mayor of London Boris Johnson is currently the frontrunner to succeed Cameron, as he re-entered parliament in May. His widespread popularity with the public – and lack of connection with the coalition government – make him strong choice for Conservatives.

The Home Secretary Theresa May was at one point a strong contender as the only female candidate, but in recent months her chances have been gradually slipping away to her competitors. Her leadership bid looks less and less credible in a field swarmed with other ambitious cabinet ministers.

No candidate will have to officially declare their candidacy until we are much closer to 2020, but with Cameron announcing his resignation plans so far in advance, we can rest assured that the frontrunners are already plotting to gain the support of the party.