Mr Miliband had been tipped as a possible leadership contender
David Miliband is the top choice for Gordon Brown's "Fantasy Cabinet" among viewers of the BBC's Daily Politics, Newsnight and News website users.
The environment secretary, thought to be a potential leadership challenger at one stage, scooped 1,776 nominations.
Alan Johnson was top choice for deputy PM, Jack Straw would return to the Home Office, Ed Balls would be chancellor and Hilary Benn, foreign secretary.
Among celebrity choices in the 2,900 entries were Greg Dyke and Alan Sugar.
A Cabinet reshuffle is expected on Thursday, the day after Chancellor Gordon Brown becomes prime minister on Wednesday.
There has been much speculation about who will be in, and who will be out, of the Cabinet, and there were some clear favourites among the near-3,000 "fantasy Cabinets" sent in to the BBC.
Home Office:Jack Straw
Chancellor: Ed Balls
Foreign: Hilary Benn
Health: Harriet Harman
Education: Alan Johnson
Environment: David Miliband
Defence: Des Browne
Justice: Baroness Kennedy
Culture: Tessa Jowell
Deputy PM: Hazel Blears
Harman and Blears got their posts as they were the most popular nominations for their role after everyone else who had a job was eliminated
Mr Miliband, who said in April after months of speculation that he would not run for the leadership, got the most nominations overall to enter the "Fantasy Cabinet" and was the most popular choice for environment secretary, his current job, and health secretary.
He has been given a further spell in his current job in the fantasy Cabinet because he got more votes in that role than he got to be health secretary.
International Development Secretary Hilary Benn came second with 1,719 nominations - and was the favourite to become foreign secretary.
Commons leader Jack Straw picked up 1,714 nominations overall and was the favourite to return to the first job he held after Labour's 1997 victory - home secretary - a role which is being vacated by John Reid.
And Alan Johnson, who narrowly missed out on the post as Labour's deputy leader, was the favourite to take on John Prescott's other role, as deputy prime minister.
He was also top choice for his current job, education secretary, in the Fantasy Cabinet.
Because both Mr Johnson and Mr Miliband could not serve in dual roles, the health and deputy PM roles were allocated to Harriet Harman and Hazel Blears, who had the most votes after other Fantasy Cabinet members were discounted.
Mr Brown's close ally Ed Balls would step into his shoes at the Treasury, Tessa Jowell and Des Browne keep their jobs as Culture Secretary and Defence Secretary and Labour peer Baroness Kennedy QC is the favourite for Justice Secretary.
Among the most popular choices from outside the current Cabinet and ministers, were former Labour minister and prominent anti-war campaigner Tony Benn, Tory frontbencher and TV favourite Boris Johnson, Top Gear host Jeremy Clarkson and Conservative leader David Cameron.
Boris Johnson was among Tories nominated for the fantasy Cabinet
Some backed a role reversal - putting outgoing PM Tony Blair in as chancellor - others backed a return to the Cabinet for former home secretary Charles Clarke, who last year apologised after accusing Mr Brown of being a "control freak".
Several readers would have Mr Brown poach other prominent Tories, including former PM Lady Thatcher as education secretary, frontbenchers William Hague and Dominic Grieve and Ann Widdecombe.
Former Lib Dem leader Paddy Ashdown, who turned down the post of Northern Ireland secretary when Mr Brown offered it to him last week, also picked up several nominations.
And Lib Dem leader Sir Menzies Campbell, DUP leader Ian Paisley and SNP leader Alex Salmond were all among readers' choices for fantasy Cabinet jobs.
Other unusual possibilities included Greg Dyke - who stepped down as BBC Director General after the Hutton inquiry - as culture secretary and Amstrad boss Alan Sugar, or "rogue trader" Nick Leeson, as chancellor.
Perhaps the most unlikely Fantasy Cabinet ministers were World War II prime minister Winston Churchill, comic book superhero Spiderman, Slade frontman Noddy Holder and TV gardener Charlie Dimmock.