Harriet Harman became the surprise victor in the race to succeed John Prescott, snatching victory from Alan Johnson by less than one percentage point in a campaign in which she picked up votes by brandishing her left-wing credentials.

Gordon Brown moved quickly to limit her influence as Labour’s new deputy leader, announcing that she would have a party role rather than a top government job, and would not succeed Mr Prescott as Deputy Prime Minister.

Aides said that she would not deputise for Mr Brown at Prime Minister’s Questions, and she is not expected to follow Mr Prescott’s lead by taking charge when Mr Brown goes on holiday.

The result took Mr Brown by surprise, with Ms Harman overtaking Mr Johnson, the Education Secretary and bookies’ favourite, in the final round of voting to win by 50.43 per cent to 49.56 per cent.

Although Mr Johnson was ahead among MPs, MEPs and trade unions in the final round, Ms Harman’s decisive 10,851-vote lead among party members handed her victory.

The Justice Minister, who was demoted from the Cabinet in 1998, became the 16th deputy leader of the Labour Party and the second woman, after Margaret Beckett, to hold the post.

Jon Cruddas, the backbench MP with strong union ties, played a key role in her victory, with almost three quarters of his supporters among the party membership choosing her second over Mr Johnson.

Mr Cruddas, who had been virtually unknown at the start of the campaign, was in the lead after the first round of voting, but lost out because he picked up fewer second-prefer-ence votes than his rivals. He was congratulated by union leaders for coming third and for raising the profile of the issue of housing – a key theme in Mr Brown’s speech yesterday.

Hazel Blears, the current party chairman, who was standing on a Blairite ticket, was the first of the six contenders to be eliminated, scoring badly among both party members and trade unions despite the support of a number of high-profile MPs, including John Reid and Tessa Jowell.

Peter Hain, the Northern Ireland Secretary, went out next after failing to pick up support among members. Hilary Benn, the International Development Secretary and one-time front-runner, came fourth overall, principally because of lack of support among MPs and MEPs.

Mr Brown, Tony Blair and Jack Straw, the Chancellor’s campaign manager, did not vote in the election. The support of other leading Brownites was split between Mr Johnson, who was backed by Ed Balls, the Chancellor’s right-hand man, and Ms Harman, who was backed by Douglas Alexander, the Transport Secretary.

The result also provoked concern in some parts of the party, with one Cabinet Minster giving warning: “[A Harman victory] would be a throwback to the past. I would sooner leave the country than watch her deputise for Gordon at Prime Minister’s Questions.”

During the campaign Ms Harman said that she was concerned about the widening gap between rich and poor. In a televised debate between the candidates on Newsnight on BBC Two, she said: “Do we want to be a divided society where some people struggle and others spend £10,000 on a handbag?” She also suggested that she wanted to revive the royal commission on the distribution in income and wealth to look at the issue.

In her acceptance speech Ms Harman said that the deputy leadership contest had been good for the party because members had spelt out how they wanted politics to change.

“During the campaign I heard what you said – and you want action to tackle the shortage of affordable housing, to do as much for youth services as we’ve done for children under five, to ensure better support for families with older relatives, to guarantee equal treatment in the workplace and action to improve our environment,” she said.

In a swipe at Mr Blair’s style she said: “You want our plans to be debated and presented to Parliament, not briefed and spun to the media.”

Rise, fall and rise

— Harriet Ruth Harman was born in London on July 30, 1950. She was educated at the exclusive St Paul’s Girls’ School before going on to study law at York University

— She worked for the National Council for Civil Liberties (now Liberty), and became a QC in 2001

— Ms Harman, who sent her three children to selective state schools, has made much of her new Labour appeal as a southern woman. She claims she can counterbalance Mr Brown’s male Scottishness

— The veteran women’s rights campaigner is also a long-standing part of the old Labour establishment. She was elected as MP for Peckham (now Camberwell and Peckham) in 1982, and sat on the opposition front bench throughout the radical years that followed

— Her husband is Jack Dromey, the party treasurer and deputy general secretary of the Transport and General Workers’ Union

— As Constitutional Affairs Minister, she was forced to give up the Lords reform and electoral administration parts of her brief to avoid any conflict of interest when Mr Dromey revealed in March an investigation into union loans made to the party apparently without officers’ knowledge

— Ms Harman was sacked as Social Security Secretary in the first Blair Cabinet in 1998 amid a row over cuts to lone-parent benefits. She made a comeback in 2001 as Solicitor-General, but after the 2005 election was moved to her current job as Justice Minister

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