Business leaders attending the annual conference of the British Chambers of Commerce in Birmingham gave an overwhelming vote of confidence to the Labour leader as he spelt out the party's plans on taxation, the economy, labour relations and education, trade and Europe.
Delegates said that Mr Blair had received a warmer welcome than the President of the Board of Trade, Ian Lang, who spoke on Tuesday, and had gone a long way to laying the ghost of Labour's interventionist past.
In a foretaste of Labour's Road to Manifesto document being unveiled today, Mr Blair pledged that its economic policy once in power would be based on "save and invest, not tax and spend".
He repeated his pledge to work for sustainable non-inflationary growth, saying Labour would set and stick to an explicit low target for inflation and would not indulge in a dash for short-term growth.
He also pledged that although Labour supported the Social Chapter and a minimum wage, any new measures would only be introduced after consultation with business and if they enhanced Britain's competitiveness.
On regulation he promised a "lean but effective" regime which did not tie business up in unnecessary bureaucratic knots. Labour would also be in the forefront of promoting free trade and opposing protectionism while it would give Britain a leading role in determining Europe's future.
But above all Mr Blair sought to persuade his audience that Labour's economic policies would not alter once in power and that the idea of the hard left just waiting until it got into office to reverse its policies was "ridiculous".
He said: "We say what we mean and we mean what we say. The old ideologies are dead. The traditional divisions between left and right over business are a thing of the past."
He said it was fundamentally unhealthy that business had a history of siding with one political party against another. But there had been a transformation in the understanding and trust of Labour in the business community.
Robin Geldard, the past-president of the British Chambers of Commerce, said afterwards that Mr Blair had done much to allay the fears of the business community although his successor, David Richardson, cautioned that the Labour leader's ability to hold the line might depend on the size of his majority.
Bob Moore of the Birmingham Chamber of Commerce, said that Mr Blair had received a warmer response than Mr Lang and had captured the mood of optimism. "What we saw today was a pragmatic and professional approach. There is an increasing sense that business would be comfortable working with either party," he said.
John Townsend, chairman of the Association of East Midlands Chambers of Commerce and Industry, said: "Blair is convincing quite a body of the business community that Labour is a party with which we can work. There is nowhere near the apprehension that there was only five years ago." Other delegates went further, saying that the Labour leader had moved directly into territory occupied by the Conservatives and that fears about the Social Chapter were vastly overstated.
Roger Charnley, chief executive of the Lincolnshire Chambers of Commerce said that businessmen there already had experience of a Labour-controlled City Council in Lincoln and it had worked well. "If there is to be a Labour administration we would seek to work with it."