Gordon Brown tried to revive his party yesterday with a conference speech packed with policy announcements designed to appeal to middle-class voters and prove that he had not run out of steam.

The Prime Minister promised to remodel the economy, clean up politics and create a more responsible society during a defiant performance in Brighton in which he set out the lines on which the looming election battle will be fought. He told MPs and delegates not to give in to defeatism but to “dream big dreams”.

He conceded that two of Labour’s most cherished policies had failed. He admitted that relaxing the licensing laws had not been a success and gave councils the power to ban 24-hour drinking. He also confirmed that compulsory ID cards had been scrapped.

He said that Labour would cut costs and “make savings we know we can”, but gave little detail, instead promising to increase child benefit and ringfence spending on schools and international aid. He also announced:

• a referendum to replace the first-past-the-post electoral system with the alternative vote system;

• a £750 million programme to provide free home care for elderly people with dementia;

• plans to put teenage mothers on benefits in supervised hostels;

• free childcare for 250,000 two-year-olds from poorer families, to be paid for by scrapping tax relief on care.

Mr Brown was introduced by his wife, Sarah, and warmly cheered by an audience that clearly regarded him as an underdog in the coming poll, which will almost certainly be held on May 6. In a tacit recognition that some MPs have already conceded defeat, it emerged that Labour would deny special funding to candidates deemed not to be working hard enough.

The view among most MPs and ministers was that Mr Brown had done enough to make an attempt to remove him this autumn less likely. Tony Blair has spoken at length to Mr Brown recently and is expected to play a role in Labour’s election campaign.

By outlining a series of political, economic and social reforms, Mr Brown was sending out the message that Labour meant change for the majority and the Tories for the privileged few.

It was clear that advisers had decided to contrast his serious approach with the alleged shallowness of the Tory leadership. But there was highflown rhetoric. He said that Labour were “the fighters and believers — we have changed the world before and we are going to do it again”. He urged them “to fight to win for Britain”.

His campaign suffered a blow last night after The Sun, Britain’s best-selling daily newspaper and a sister paper of The Times, decided to throw its support behind the Tories. It supported Labour for the past three elections.

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