His remarks amount to the clearest appeal so far to Mr Blair to heed the anxieties of the grass roots about the pace of changes being inflicted upon the party.
In an exclusive interview with the Independent before leaving for a fortnight's break in America, the Labour deputy leader also warned Mr Blair that the party was "uneasy" about the pace of change. Party unity was being stretched so much, he said, that MPs had voted for people "they couldn't stomach'' in the recent Shadow Cabinet elections.
Mr Prescott, who yesterday left for a holiday with his wife, Pauline, in New England before attending the Democrat convention in Chicago, wants Labour to avoid American-style negative campaigning.
"The success in rebutting lies is one thing - there are some things you can use - but British politics is more about substance of ideas and less about the image, though I fear we are drifting in that way.
"I think this election has got to be about ideas, principles and substance and not simply image, because that is the one thing that unites all parts of the party.
"You need an enthusiastic party amongst the converted, the returning ex-Labour voters. I hope to provide that role.
"I have tried to do that with the Spirit of '45 [a pamphlet highlighting New Labour's links to the post-war Attlee government which introduced the Welfare State]."
Mr Prescott said it had been intended to emphasise the continuity - "here's our principles and our ideas; they are connected; they are not uncoupled; they are as one. It's Labour changing through its phases, dealing with different problems, which I called traditional values in a modern setting.
"Providing we still can judge our policies against that and not necessarily against soundbites and headlines, then I think you can carry both.
"The party has had more discussion about change than it has ever had before. There is an uneasiness about change, as when change follows change, follows change. Sometimes policies seem to appear rather quickly. I think this has left the party feeling a little uneasy. But overwhelmingly, the party wants to win the next general election.
"That is Tony Blair's overall consideration. All of us will look at the political environment in which we are operating. We don't operate in iso- lation. It isn't really the case that Tony Blair dictates the position - he is a person who desperately tries to find an agree- ment. He is the leader. Leaders are controversial."
The deputy leader admitted he had had disagreements with Mr Blair, but they were mainly over Labour's press coverage.
He had persuaded Mr Blair to go ahead with the Shadow Cabinet elections in which Harriet Harman was re-elected, and Mr Prescott was responsible for "heading up a team to see that people voted for the status quo.
"That was one of the greatest acts of discipline by the parliamentary party that has ever been recorded. There were lots of MPs voting for people they couldn't stomach, but they did not want to provide division. They knew the importance of it. It was not given proper recognition."
Mr Prescott has gone on holiday after showing his loyalty to the leadership in dismissing the concerns raised by Ms Short. But he has become convinced of the need to exercise more influence over the direction of the party in the run-up to the general election.
Mr Blair is planning to use the Road to the Manifesto campaign to answer some of the criticism about Labour's unease over the pace of change.