Old hands and young Turks: the contenders for PM's crown

JACK STRAW Justice Secretary

Shrewd, experienced and pragmatic, Straw is uniquely qualified to deliver bad news to Gordon Brown.

MPs universally name him as the leader of any delegation to tell the PM his time is up. At 61, he has four decades of high-level politics under his belt, and has held three great offices of state: Home, Foreign and Lord Chancellor. Some call him the Real Deputy Prime Minister.

Handled the transition from Blair to Brown brilliantly, emerging stronger. In recent months he is said to have become frustrated with Brown. The prize for wielding the knife might be to become caretaker premier or a heavyweight Deputy PM. If he dithers, he risks being supplanted as Cabinet greybeard by Margaret Beckett.

Critically, his majority is only 8,009 in Blackburn. If things don't get better, he could lose his seat.

Leadership odds: 4-1
Danger rating:

GEOFF HOON Chief Whip

Although doggedly loyal in public, Labour circles are rife with gossip that Hoon is disenchanted with Brown's style.

They are said to have had tense relations during the 42-day revolt, when Hoon allegedly felt the PM was trying to micro-manage negotiations with rebels.

There is talk of the Chief Whip firing off a three-page memo later telling No 10 what it must do to improve its operation, though his aides deny it.

There is also gossip that Hoon himself was being undermined by a rival whip's office led by his deputy, ¸ber-Brownite Nick Brown.

Hoon is adamant he will oppose any plot against Brown. Cynics say that's because he hopes to be made a European Commissioner.

Leadership odds: 33-1
Danger rating:

DAVID MILIBAND Foreign Secretary

The most senior Blairite in Cabinet is a reluctant assassin.

Last year he famously declined to throw himself in front of Gordon Brown's leadership bandwagon. When Tony Blair was asked why Miliband ducked the contest, the then-PM replied: "He is scared of what they would do to him."

A year later, the 43-year-old is still the great white hope of Blairite diehards. Several Left-wingers back him, too, seeing the articulate moderniser as a young candidate who could cut David Cameron's gains. Although geeky, he has a gift for explaining complex policies.

Leadership odds: 5-2
Danger rating:

JAMES PURNELL Work and Pensions Secretary

A rising star of just 38 who is often compared to a young Tony Blair.

His credibility was boosted by his recent welfare reform Green Paper, brilliantly spun to sound ultra-tough. He has said he would not run against David Miliband - which infuriates Brownites and raises the pressure on Miliband not to duck a second chance.

Many MPs see him leading them out of the wilderness in five to 10 years.

Leadership odds: 7-1
Danger rating:

HARRIET HARMAN Deputy Labour Leader

Often under-estimated, the feisty Ms Harman should not be overlooked.

Fiercely ambitious, she has been eager to be given more responsibility, and is said to fire off constant memos about how to raise the Government's campaigning performance.

Many expect her hat to be in the ring if Gordon Brown goes - the question to answer is how hard she would fight to save him.

Although articulate and attractive, Ms Harman's critics say she is not subtle enough for high office. And Mr Brown may strip her of some jobs in a September reshuffle.

Leadership odds: 12-1
Danger rating:

ALAN MILBURN Former Health Secretary

Usually linked with Stephen Byers and Charles Clarke as a trio of ¸ber-Blairite ex-ministerial plotters.

As a minister and later as party chairman Milburn clashed bitterly with the then-Chancellor and lost, retiring to the backbenches.

Intriguingly, before making a recent speech on social mobility, Brown telephoned Milburn to read over a section and ask him what he thought. Could Milburn rejoin the Cabinet in September?

Leadership odds: 16-1
Danger rating:

GEORGE HOWARTH Former Home Office minister

Clumsy plotter who was rumbled when he approached an MP to say he was "collecting names for Jack".

Howarth is dismissed by Brownites as a nobody who nurses a hatred of the PM. Actually, that makes him very dangerous indeed. The MP denies that he was collecting names for a letter that Jack Straw would show to Brown.

Leadership odds: n/a
Danger rating:

TONY LLOYD Chairman of the Parliamentary Labour Party

The "shop steward" of Labour backbenchers is a powerful influence over the PM's future.

Lloyd can claim to be the voice of the ordinary MP, which means any delegation to No 10 that failed to include him would probably fail. At the same time, every statement he makes is scrutinised for signals that Brown is in trouble.

Leadership odds: n/a
Danger rating:

CHARLES CLARKE Former Home Secretary

When MPs ask who will throw the first stone, Clarke's name invariably comes up. Utterly blunt, the heavyweight led the anti-Gordon brigade when he was in Cabinet and is said to have begged David Miliband to run against him.

Brown offered Clarke a non-government job, but Clarke backed out, keeping himself free to hurl rocks from the side.

Leadership odds: 40-1
Danger rating:

ALAN JOHNSON Health Secretary

He considered running against Brown in 2007 and is now being touted as a late substitution.

The former trade union official has been scrupulously loyal in Cabinet but has strong support among MPs.

His record is blighted by two big errors. He once rashly admitted he was not cut out to be PM. And he failed to beat Harriet Harman in the deputy leader race. Nevertheless, he is third favourite at the bookies.

Leadership odds: 5-1
Danger rating:

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