Elder son of the Marxist theorist Ralph Miliband, the South Shields MP and foreign secretary was Tony Blair’s protege and head of policy for the Labour party at the age of 29. He went on to head up Blair’s policy unit in Downing Street after the 1997 election. He is admired in the upper echelons of the Liberal Democrat party but lost face when he U-turned on a leadership bid two years ago.
USP A favourite with the metropolitan elite, seriously brainy and has the experience of a big cabinet brief in the Foreign Office.
Biggest hurdle His biggest challenges are to convince the Labour party grassroots that he will serve their needs, to prove he is more than a brainy academic and that he has popular appeal.
Photograph: Andrew Winning/Reuters
Who is he? The home secretary, who is the most Lib Dem-friendly of the leadership contenders having been a long-term supporter of electoral reform. A former postman and trade union leader, he is a rare beast in that he is a working-class Blairite and popular in the party, particularly among the unions.
USP The voter-friendly caretaker choice. Biggest hurdle Not sure he wants the job – and doubts about his clout.
Who might back him Broad-based support within the parliamentary party and strong union support.
Photograph: Andrew Winning/Reuters
Who is he? The younger Miliband brother, current environment secretary, was the author of the election manifesto. He is a possible dark horse candidate for the leadership, having only entered parliament in 2005, but garnering support within the party.
USP He’s a brilliant media performer, accomplished at giving speeches and also has sound economic experience as a former treasury adviser to Brown.
Biggest hurdle Few people have heard of him and as being the less likely brother to enter the race he could be blamed for the obvious comparisons that will inevitably be made in the fraternal fight for the leadership.
Who might back him Close to Gordon Brown. Some see him as more approachable than his older brother. MPs with green in their veins.
Photograph: martin argles/Guardian
Who is he? The hugely energetic schools secretary and former adviser to Brown since 1994. When Brown became prime minister Balls was made education secretary, a job that put him on the frontline of the public face of Labour. He has the strong backing of the trade unions and will be able to deploy an extensive campaigning team to aid his bid.
USP He will argue that his experience in the Treasury places him head and shoulders above the others to tackle the economic crisis. He has a high public profile after doing the schools job.
Biggest hurdle His public profile is divisive. He has to recast himself to lose the image of class warrior and close association with some of the bully-boy briefing tactics of the Brown era.
Who might back him Brown in private, if not in public; the big unions; Derek Simpson, the joint general secretary of Unite.
Photograph: Dominic Lipinski/PA
Who is he? The centrist health secretary, former culture secretary and chief secretary to the Treasury, he has risen swiftly through the ranks and is strongly rooted in the Labour party.
USP Telegenic and personable, he has broad experience across government.
Biggest hurdle Despite sound experience, perhaps seen as a little lightweight.
Who might back him Worked for Tessa Jowell, Chris Smith and a union before entering parliament.
Photograph: Antonio Zazueta Olmos/Guardian
Who is he? The left candidate, he was deputy political secretary to Tony Blair, working as the link between the PM and trade unions from 1997. He worked heavily on the introduction of the minimum wage, but later rebelled over top-up fees, changes to the comprehensive system and Trident. He has experience in Labour leadership contests after he ran for deputy leader in 2007, but lost to Harriet Harman.
USP Firmly leftwing candidate appealing to the left of the party – he turned down cabinet jobs under Brown to maintain his independence as a backbencher.
Biggest hurdle Raising a profile, shifting the party away from the centre.
Who might back him The unions, the left of the party but also Tony Blair. He worked closely with David Miliband in No 10 and there have been some suggestions that he run as Miliband’s deputy.
Photograph: Richard Saker/Richard Saker
