Ed Miliband says it's time to 'move on' from Blair
Ed Miliband has said it is time for Labour to "move on" from Tony Blair - as the former PM warns against rejecting New Labour reforms.
Mr Miliband told the BBC he was the best placed candidate to "turn the page" and said the party should not "live in the past".
His brother David has won the Labour-supporting Mirror's backing - as ballot papers are sent out to party members.
Mr Blair has not backed a candidate but is believed to favour David Miliband.
Asked whom he would back by the BBC's Andrew Marr, in an interview to be screened later, Mr Blair said: "It may be fairly obvious, and I'm not saying it isn't."
'Courage to change'
But he said, whoever was elected, "even if it's Diane [Abbott] they will have my 100% support".
In an interview with the BBC, Ed Miliband said both Mr Blair and Gordon Brown had been "fantastic servants for our party and our country", but it was time to "move on from the New Labour establishment".
He said the party had lost five million votes since its 1997 general election landside, and Labour had to have the "courage to change" in order to win back power.
Mr Blair suggested in his memoirs, published on Wednesday, that Labour had lost the 2010 election because it had backed away from further New Labour reforms and told the BBC it had to stay at the "cutting edge for the future in public services".
But Ed Miliband dismissed the idea that the party has to embrace New Labour ideals if it was to win the next election: "I really think we've got to move on from the politicians of a previous generation. We honour the contribution that they have made to our country and our party, but we don't live in the past. It's only by moving on that Labour can reconnect with people."
Voting in the contest to succeed Gordon Brown is now open to Labour Party members, and members of affiliated trade unions and socialist societies. The winner will be announced on September 25.
While acknowledging that Ed had been the "big surprise" of the leadership campaign, the Daily Mirror has decided to back his brother David.
The paper highlights the former foreign secretary's experience at the highest level of government, and says the Tories "really fear" him.
'Warm comradely contest'
Both brothers have said they would be prepared to serve under the other.
David insisted that the election campaign had been "a warm, comradely contest, a fraternal contest and... a contest that I think will bring credit to the Labour Party and will certainly not come in the way of our family."
The brothers are keen to draw a line under a war of words which has broken out between their respective supporters.
Lord Mandelson, who has made little secret of his preference for David, sparked the clashes by warning that the party would be stuck in an "electoral cul-de-sac" if it opted for a "pre-New Labour" agenda.
But Lord Kinnock - a supporter of Ed - hit back by accusing the former business secretary of being "sadly out-of-date" in suggesting there could be no deviation from the strategy which won Tony Blair three terms in office.
Leadership rival Ed Balls warned that the Miliband "soap opera" was in danger of drowning out debate over the party's future policy agenda.
He insisted it "does not matter a jot" who gets Mr Blair's support and said his former mentor Gordon Brown was "doing the right thing" in keeping his cards close to his chest.
In his newly published autobiography, Mr Blair's verdict on Mr Balls was decidedly mixed: "I've had some harsh things to say about Ed Balls - I thought he behaved badly at points, and was wrong on policy - but I also thought he was really able, and a talent that any political party should be grateful to have."
The shadow health secretary Andy Burnham, meanwhile, has also rejected any suggestions that the leadership contest is a two-horse race between the Milibands. He said he was "in a strong third position and gaining ground" on his rivals.
Meanwhile the other leadership contender, backbencher Diane Abbott, has criticised Mr Blair's remarks about Gordon Brown in the book: "I'm surprised Tony Blair couldn't have waited a decent interval before putting the knife into Gordon Brown. It's not helpful to the party at this point."
Nearly a million people voted in the last contested Labour leadership election, in 1994.