All they have achieved, he claims, is being more adept at using the "tactics of using media and parliament to harry the government".
"Most Tory supporters, whatever they feel about the government, must be deeply confused about the direction of their own party," the prime minister said.
Although the Labour government has been plagued with controversy over the Iraq war, NHS pay and reform and Trident as well declining support – a Populus opinion poll this week placed Labour on just 29 per cent, the lowest since Mr Blair became leader – he insisted that Labour are "the best people" to govern.
"We still have the right vision for Britain's future," Mr Blair said.
"We still have the policies that are thought through. We have ten years of achievement. But there is more to do; new challenges to take on; fresh changes to make. We are the best people to do it."
Speaking in support of Mr Cameron last night, former Conservative leader Sir John Major said he had "genuine political stardust" and could be the next prime minister.
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