David Miliband is set to be the new Labour leader, edging out his younger brother Ed in what is becoming a two-horse race, according to a new poll.
The YouGov survey for The Sun predicted that the Milibands will leave rivals Ed Balls, Diane Abbott and Andy Burnham trailing to claim the first two places in Labour's electoral college of MPs and MEPs, party members and affiliated organisations including unions.
When the defeated candidates' votes are redistributed, shadow foreign secretary David would beat shadow energy secretary Ed by a margin of 54% to 46%, the poll found.
Asked about the findings, Ed Miliband declined to accept the race was over, telling BBC Two's Newsnight: "I will congratulate whoever the winner is when the result is announced on September 25."
Analysing polling of a total of almost 2,500 Labour members and trade unionists, as well as recorded declarations of support by MPs and MEPs, YouGov found that David Miliband would take 37% of the electoral college vote in the first round, followed by Ed Miliband on 29%, Ms Abbott and Mr Burnham on 12% and Mr Balls on 11%.
David Miliband would secure the largest share of the vote in all three sections of the electoral college, with 39% of MPs and MEPs, 38% of activists and 34% of members of trade unions, YouGov found.
Some 52% of party members said David Miliband was the candidate most likely to lead Labour to victory in the next general election, while 41% said he would make the best prime minister and 40% that he would be most effective in holding the Government to account as leader of the opposition.
Ed Miliband came out on top as the most likeable candidate, with 29%, and the one who best reflects members' views, with 24%, while Mr Burnham was viewed as the candidate most in touch with ordinary people's lives, on 22%.
The poll suggested that Labour members are ready to compromise on ideology in order to get the party back into power.