It is time for Labour to move on from Blairism, one of the contenders for the party's deputy leadership has said.
Mr Cruddas is among seven potential deputy leader candidates
Speaking to BBC One's The Politics Show, Jon Cruddas said the "magic" of Tony Blair's early years had changed into an "extraordinary" resilience.
The left-wing candidate said: "The page has turned, it's time to move on."
Meanwhile former home secretary Charles Clarke has said Gordon Brown is increasingly likely to face a contest to be the next Labour leader.
The prime minister and the deputy prime minister John Prescott are due to stand down by September this year.
"Ten years is an awfully long time to be prime minister of any one country," Mr Cruddas told The Politics Show.
"That sort of magic of the early years has changed into a sort of resilient durability, which is very impressive, irrespective of whether you agree with it or not.
"I mean, the stuff he takes is extraordinary."
New Labour agenda
An aide to Mr Cruddas said the Dagenham MP and former Downing Street adviser felt Labour needs to "refresh itself".
Mr Cruddas has previously said the party needed to reconnect with the electorate.
His comments come after Mr Blair appealed for party activists to keep faith with the New Labour agenda.
Mr Clarke said Gordon Brown should set out a 'clear vision'
Hilary Benn, Hazel Blears, Peter Hain, Harriet Harman, Alan Johnson and Jack Straw are the other MPs to officially declare, or indicate, an interest in the deputy leadership post.
On Sunday Mr Clarke told Sky News that Gordon Brown, the favourite to succeed Mr Blair, should set out a clear vision for the country - and was increasingly likely to face a challenge.
"I think there may very well be a contested election but the fact is that whether there is or not depends on addressing this policy agenda," he said.
"And I think the best way that Gordon could secure his future would be to address that policy agenda - I am disappointed he hasn't done so far - and I hope he'll begin to start doing that."
Former Labour cabinet minister Tony Benn said a contest was needed to give party members and the trade unions a chance to vote when Mr Blair finally steps down.
He also claimed that if leadership contender John McDonnell, MP for Hayes and Harlington, is not nominated, then party members will have been "shut out".
Mr Benn told GMTV's The Sunday Programme: "If MPs refused to nominate John McDonnell for example... and deny the party a choice, then Gordon Brown will not have been elected and will have no authority.
"There must be an election. If it turns out that the Labour Party have a coronation, I mean we might as well have a heredity leader of the Labour Party."
The Politics Show is on BBC One at 1200 GMT on Sunday.