EU referendum: Who is Steve Hilton – the former Cameron aide backing a Brexit?

Westminster village outsiders are likely to have no clue who Steve Hilton is, but his support for a 'Brexit' at the EU referendum has hit the headlines. That is because Hilton is often credited as one of the architects of David Cameron's rise to power.

The Oxford University graduates (both studied politics, philosophy and economics) first met working for Conservative Party Headquarters (CCHQ) during the 1992 General Election campaign, which saw John Major secure a surprise victory.

Hilton later went into advertising at Saatchi and Saatchi and found infamy at the next general election as the man behind the "Demon Eyes" poster. The campaign depicted a menacing looking Tony Blair with the caption: "New Labour, New Danger".

With the Conservatives cast into the political wilderness and the New Labour project going strong, Hilton apparently voted Green in 2001.

But he would be brought into the Tory fold after Cameron's election as leader in 2005. There the "pint-sized Rasputin" – owing to Hilton's casual dress sense, small stature and strong influence over the future prime minister – would work his magic.

Cameron, Hilton and George Osborne would set about detoxifying the Conservative brand. Successive leaders, including Iain Duncan Smith and Michael Howard, had attempted to take on New Labour with socially conservative policies but failed to woo the British electorate. Hilton and his acolytes realised the party would have to modernise if it wanted to see a Tory PM back in Number 10 again.

Soon there was talk of the "Big Society", the third sector stepping in to help the worse off rather than the State, and Cameron began trumpeting environmental policies, with the Old Etonian even travelling to Norway to pose next to huskies in the antarctic to warn about global warning. The party's torch logo would also be scrapped for a green tree, an exercise which reportedly cost £40,000.

Success in the centre

The shift to the centre group of politics was not without its critics, with Conservative traditionalists taking aim at Hilton and Cameron, but the move enabled the Tories to broker a power-sharing deal with the Liberal Democrats after the hung parliament result of the 2010 general election.

Hilton was later parodied as "blue-sky thinking" Stewart Pearson in cult satire favourite, The Thick Of It. The husband of Silicon Valley high-flyer Rachel Whetstone (formerly Google, currently Uber), took a year-long sabbatical from Number 10 in 2012 to become a visiting fellow at Stanford University's Hoover Institution.

He would later leave Downing Street and co-author the 2015 More Human: Designing A World Where People Come First, "a manifesto and call to action for a more local, more accountable and more human way of living that will make us more productive, more fulfilled and ultimately happier".

Hilton has now risked upsetting his old ally Cameron in backing a Brexit. The pro-EU prime minister faces the sack if the British electorate vote 'leave' on 23 June, but his former guru said constant meddling by Brussels made Britain "literally ungovernable".

Hilton wrote in the Daily Mail: "A democracy is based on the notion that the people — or their directly-elected representatives — are able to decide issues for themselves. And yet membership of the EU brings with it constraints on everything from employment law to family policy, all determined through distant, centralised processes we hardly understand, let alone control."

The Mail is billing Hilton's intervention as a "shattering blow" to Cameron, but will his comments register outside SW1?