David Cameron launches his campaign yesterday Witney MP David Cameron has launched his campaign to lead the Conservatives by saying the party needs to change to become trusted.

Under his campaign mantra "change to win", Mr Cameron said the Tories had to embark on a mammoth rebranding exercise in order to gain the trust of the electorate.

Yesterday's speech at the Royal United Service Institute in Whitehall, London, was carefully co-ordinated to coincide with that of rival David Davis, who also launched his bid on the party leadership yesterday.

So far Ken Clarke, Liam Fox, Mr Davis and Mr Cameron are the only Tories to have thrown their hats into the ring ahead of the Conservative Party autumn conference, which starts this weekend in Blackpool. Present leader Michael Howard will stand down at the end of the conference.

Mr Cameron said: "The trouble is that people don't trust the Conservative Party and we have got to change.

"It's not policies alone that are going to do that, it's not even having a young, energetic and vigorous party leader -- it's not about presentation, it's something much more fundamental.

"We have to explain what it means to be a Conservative in 2005.

"There is no Clause Four, there is no magic wand,but we need to change right across the board, look and feel, talk and sound like a completely different organisation.

"I want no more by-election or General Election campaigns where our message is negative and we just attack our opponents -- I want to talk about people's hopes, not their fears.

"There is a 'we' in politics as well as a 'me'. We need a shared responsibility, a sense that we are all in this together."

Mr Cameron's vision for the party was one with traditional Conservative values adapted to the demands of the 21st century.

He said a commitment to national sovereignty should not result in isolation and xenophobia and lower taxes should not look like bribes at election time and added: "Rolling back the state should never mean that the weak and defenceless are left behind."

High-profile Tories MPs like Oliver Letwin and the Oxfordshire trio of Ed Vaizey, Boris Johnson and Tony Baldry have already come out in support of Mr Cameron.