When the Labour leadership race began, the Tories immediately identified Andy Burnham as the candidate they wanted to win. The hope was that he would merely be "Miliband with a prettier face" or even tilt leftwards. But Burnham's first speech of the campaign, delivered to business leaders at Ernst & Young, showed that he may not be the Labour leader of their dreams. In the symbolic location of the City of London, the shadow health secretary declared that the party had too often failed to tell business that "we value what you do – creating jobs and wealth." Entrepreneurs, he said, "will be as much our heroes as the nurse or the teacher", countering the impression of a party concerned with the public sector alone.

In a passage reminiscent of the Tories' mantra that strong public services depend on a strong economy, he added: "Labour must always champion wealth creation, and show we understand that, if we want world-class public services, and if we want high-skill, high-wage jobs, then we must wholeheartedly support the businesses that create the revenue to pay for them." It was a signal that he would never deliver a speech in the mould of Miliband's 2011 "predators and producers" address.

He combined this attempt to reset Labour's relations with business with an admission that the deficit was too high in the years before the crash - answering the spending question that haunted Miliband in the final leaders' TV event. He criticised the party for entering the election "with business and the public unclear on how Labour will balance the books, or when we will do so." In an attempt to pre-empt Tory criticism of his past role as chief secretary of the Treasury from 2007-08, he noted that they had described the spending settlement he delivered as "tough".

Burnham's policy-rich speech - he also promised to introduce a UCAS-style system for apprenticeships and urged the government to hold the EU referendum by autumn 2016 - also saw him define his personal history and character (something Miliband struggled to do). He was, he said, "the comprehensive lad who went to Cambridge and then into the cabinet". Miliband similarly attended a comprehensive but his north London upbringing and Marxist father meant he failed to avoid being framed as an effete metropolitan. Burnham, by contrast, was able to humbly present himself as "the son of a telephone engineer and a GP receptionist who moved heaven and earth to make sure my brothers and I would be the first in our family to go to university".

His centrist pitch will make it harder for his Labour opponents to define him as the candidate of the left (a challenge for Yvette Cooper, who seeks to offer a third way between Burnham and the "Blairite" Liz Kendall) and for the Tories to do so. He may have socialist instincts on the NHS ("the public NHS is what works") and free schools (opposing their establishment in areas with surplus place) but then so do most of the public.

Burnham's greatest hindrance remains his record of service in the last Labour government. While he will have to constantly rebut Tory attacks on his past, the post-2010 Kendall would be able to avoid them altogether. But by demonstrating early on that he has learned from the failure of Labour's economic message he has strengthened his candidacy. The real test, should he be elected, would be sustaining his centrist strategy. Just as successive Tory opposition leaders promised to modernise their party but tilted rightwards under pressure, so Burnham would face pressure to head left if his approach failed to deliver early results. But by signalling that he wants to "rebuild the broad coalition of voters that put us into power in 1997" he has, for now, defied Tory caricature.