Not for the first time, Ed Miliband was following in his elder brother's footsteps yesterday when he addressed the TUC conference in Liverpool, three years after David, the Foreign Secretary, addressed Labour's brothers-in-arms.
The Energy and Climate Change Secretary wins rave reviews from the green lobby as he implements a radical policy to impose carbon budgets for each Whitehall department. Its architect was his brother when he was Environment Secretary.
Yet the word in Labour circles is that Ed is no longer trailing in his brother's wake. Indeed, some senior figures believe he has already overtaken him in the game that increasingly occupies Labour minds as the party appears to head for a general election defeat – its future leadership stakes. It is a highly sensitive subject for the two sons of the late Marxist historian Ralph Miliband. Until recently, it had been assumed that David Miliband was certain to be a contender, the most likely standard-bearer for the Blairite wing of the party. But Labour's tectonic plates are moving.
Allies of the Foreign Secretary dismiss speculation that he has twice missed his moment – by backing off a year ago after appearing to raise the flag of rebellion against Gordon Brown, and then refusing to join his ally James Purnell in a joint resignation in June which could well have brought down the Prime Minister.
On the eve of the TUC conference, Derek Simpson, joint leader of the Unite union, said in public what many Labour folk say privately when he anointed Ed Miliband as a possible successor to Mr Brown. "If I had to name one for the future I pick Ed Miliband. He has potential to be a lot more progressive," he told the Daily Mirror.
It was not the sort of praise that Ed Miliband wanted. "Look, I've been in parliament four years," he told the BBC's Andrew Marr when asked if he could be a leadership contender.
The leadership question is doubly difficult for Ed Miliband, who has instructed his staff not to even speculate about it. He could not entertain a move to topple Mr Brown, for whom he worked as an adviser before becoming an MP. And he feels equally loyal to his brother, whom he would feel duty bound to support in a leadership contest after Mr Brown had stood down.
Yet friends are quietly telling him that David will not be leader because he is seen as too Blairite. In contrast, Ed Miliband is seen as on the party's soft left, and could be in a strong position to capitalise on a reaction against New Labour that would probably follow an election defeat. Nor is he seen as too close to Mr Brown.
"Whether he likes it or not, people are buying shares in him," one friend of Ed Miliband said yesterday. "And they are selling them in David."
Ed Miliband does not want to eclipse David. He finds it difficult to imagine himself overtaking him and could not stand against him.
Sceptics say that Ed Miliband still has a lot to learn and is not ready for the top job yet. Yesterday's speech to the TUC was received politely but he was momentarily wrong-footed when his reference to the Vestas wind turbine plant on the Isle of Wight, which closed last month with the loss of 425 jobs, provoked a heckle from the audience. Campaigners at the back of the hall held up placards in support of the workers, earning a standing ovation from delegates. Mr Miliband was left applauding awkwardly on stage.
David Miliband's allies insists he would still be a strong runner in a leadership race and dismiss Westminster gossip that he is losing interest in the top job and might even be tempted by a job on the European or world stage after his spell at the Foreign Office.
Friends say he has lots of ideas, based on empowering individuals, to unveil in a leadership contest but cannot disclose now as he would be accused of disloyalty to Mr Brown.
Allies say it is premature to write him off. One said: "Ed's time will come. But it's David's turn first."
How the brothers measure up
Born: 15 July 1965
Education: Corpus Christi College, Oxford; Massachusetts Institute of Technology
Tony Blair's Head of Policy from 1994
Head of Prime Minister's Policy Unit, from 1997
MP for South Shields since 2001
Minister for Schools, 2002
Cabinet Office Minister, 2004
Minister for Communities and Local Government, 2005
Environment Secretary 2006
Foreign Secretary, 2007
Family: Married to Louise Shackelton, violinist in London Symphony Orchestra. Adopted two sons in United States; Isaac in 2004 and Jacob in 2007
Strengths: Useful experience in stint at Foreign Office
Weaknesses: Looks too geeky; politically, seen as too close to Tony Blair
Born: 24 January 1969
Education: Corpus Christi College, Oxford; London School of Economics
Speechwriter and researcher for Harriet Harman 1993
Speechwriter and researcher for Gordon Brown, 1994
Appointed special adviser to Brown, 1997
Appointed Chairman of Treasury's Council of Economic Advisors, 2004
MP for Doncaster North, elected 2005
Minister for Cabinet Office 2007
Secretary of State for Energy and Climate Change 2008
Partner: Justine Thornton, a barrister.
Strengths: More telegenic than his brother
Weaknesses: Lack of experienceReuse content