Britain's opposition Labour Party chose former energy secretary Ed Miliband as its new leader today after a cliffhanger vote.
Mr Miliband (40) defeated his older brother David, a former foreign secretary, by a wafer-thin margin to take over the helm of the party.
He succeeds former prime minister Gordon Brown who resigned after the party lost the May election, ending 13 years in power.
David Miliband was favoured by centrists in the party whereas Ed has slightly more left-leaning views and won the backing of major trade unions who help finance the party.
Mr Miliband won in the fourth round of the vote count, by a margin of a little over one percent, to steal the prize that had seemed within the grasp of his older brother for much of the leadership campaign.
"David, I love you so much as a brother and I have such extraordinary respect for the campaign that you ran - the strength and eloquence that you showed," Mr Miliband said in a heartfelt message to his brother.
"I have to unify this party and I will," the winner, who was propelled to victory by strong union backing, told party activists gathered for their annual conference in the northwestern city of Manchester.
"Today the work of the new generation begins," he said.
The new leader's focus will be on fighting deep public spending cuts planned by the ruling coalition which Labour says threaten public services and will hit the poor hardest.
The Conservative-Liberal Democrat coalition formed after the May election blames Labour incompetence for Britain's record peacetime budget deficit and says it must take urgent action to eradicate it or risk a loss of investor confidence in Britain.
Voting closed on Wednesday in the complicated electoral college race, where MPs and MEPs have one-third of the vote, with rank-and-file party members and up to three million trades unionists who pay a political fee to Labour sharing the rest.
Both brothers served in the cabinet in the New Labour days, with David an ally of Tony Blair and Ed an adviser of his successor, Gordon Brown.
Friends of David Miliband had suggested he could take a break from frontline politics if he loses, in order to avoid being painted as a rival to his brother – although he has said he is willing to serve in the shadow cabinet – elections for which open now – if he loses.
Ed Balls, one of the other three candidates, had made a strong pitch to become shadow chancellor of the exchequer.
David Miliband had stayed closer to the New Labour agenda during the campaign, refusing to commit, for instance, to attend a rally against the Conservative/Liberal Democrats proposed cuts. He has also argued that the deficit should be cut as fast as has been agreed by New Labour under proposals brought to cabinet by chancellor of the exchequer Alistair Darling.
Ed Miliband, meanwhile, has enjoyed the endorsement of the big unions and pushed for greater equality in British society.
He wants permanently increased tax rates for the rich, rather than short-term penalties such as Labour’s bankers’ bonus tax. He has voiced opposition to the Iraq war – even though he was an adviser to Mr Brown during this period and did not voice any opposition then.
Labour meanwhile, as expected, has chosen former London mayor Ken Livingstone over former Labour MP Oona King to run in 2012 in the mayoralty race against sitting Conservative Boris Johnson.
“Today’s decision signals the start of a campaign to protect London from cuts,” Mr Livingstone told supporters. “[This is a] chance to send a message that we don’t want devastating cuts. We will stand up for London. We need to change the mayor. If you want to get them out, you start by getting out Boris Johnson.”