Read the Sunday Times-YouGov poll results in full

GORDON BROWN’S opinion poll lead has halved in the space of a month, making an early election much less likely, according to the latest Sunday Times-YouGov poll of more than 1,800 people.

While Labour enjoys a five-point lead over the Conservatives, it has slipped three points from 42% to 39% while the Tories have climbed from 32% to 34%. The Liberal Democrats, on the eve of their party conference, have edged up from 14% to 15% but remain well down on their 23% share of the vote in the May 2005 general election.

The poll makes grim reading for Sir Menzies Campbell, the Lib Dem leader, who has been criticised for being too old and out of touch in comparison with rival party leaders. Asked who was the most impressive of the three leaders, only 4% named Campbell, including a minority of his own party supporters. Brown was clearly ahead with 39%, followed by David Cameron on 17%.

While 54% of Lib Dem supporters think Campbell is doing well, 27% say he is doing badly. Among all voters, only 24% say Campbell is doing well, compared with 45% who believe him to be doing badly.

Brown’s approval ratings, while down slightly on a month ago, remain strong, with 62% of people saying he is doing a good job as prime minister, against 22% who say he is doing badly.

Cameron, who had expected to do better against Brown, still lags behind the prime minister and has a negative overall rating, with 35% believing he is doing a good job as Tory leader, against 50% who think he is doing badly.

The cruellest finding in the poll is, however, reserved for Campbell. By nine to one, 45% to 5%, people said that the Lib Dems would do better if the party had a younger leader, with 38% saying that a change at the top would make little difference.

If party supporters begin to think that their disappointing poll ratings are down to a leader some see as lacklustre, Campbell could come under pressure. Lib Dem supporters already believe overwhelmingly, by 63% to 5%, that a change to a younger leader would help the party.

One threat for Brown is over the crisis in the financial markets, which led to the Bank of England’s rescue of Northern Rock last week. YouGov asked about the outlook for people’s finances over the next 12 months. Only just over a quarter, 26%, said their finances would remain healthy, compared with 50% who said they would be under some pressure and 21% who predicted that they would be under a lot of pressure.

Even before the crisis, families were being squeezed by the five interest rate rises since August last year, higher energy costs and increases in food prices. Earnings have risen at a slower rate than prices.

According to the poll, 46% of people say they will spend less on nonessential items over the next 12 months, against 12% who expect to spend more. Further increases in mortgage rates could add to the pressure, the poll suggests, with 16% expecting to face serious problems.

Despite the worries, most people do not yet expect house prices to fall. While 52% think prices in their area will continue to rise, and 28% believe they will stay about the same, only 9% are looking for price falls.

Another potential problem for Brown is over the new European Union reform treaty, which the government is expected to accept in the coming months. He has rejected a referendum on the treaty claiming it differs from the original EU constitution rejected by French and Dutch voters.

But, with some Labour MPs, the trade unions and the Tories backing calls for a referendum, the prime minister appears to be setting his face against public opinion. By 60% to 16%, voters think there should be a referendum on the treaty. Worryingly for Brown, this is also the strong view among Labour supporters, who back a vote by 47% to 28%.

Because Labour promised a referendum on the original constitution, voters believe, by 61% to 12%, that Labour would be breaking its pledge if it refuses to hold one on the treaty. As for how people would vote in such a referendum, more than a third don’t know, but of those who declared a view, 41% would reject it, with 17% in favour.

The poll also examined attitudes to the National Health Service, following Sir Derek Wanless’s report last week, which said that the NHS had not improved enough in return for the 50% real increase in spending poured in since 2002.

Only 6% think the NHS has got “much” better in recent years, while 21% say it is slightly better. In contrast, 22% say it is slightly worse and 19% much worse. By 68% to 18% they say taxpayers have not got good value for the extra money.

Last week a Conservative “quality of life” group, headed by Zac Goldsmith and John Gummer, made a number of recommendations on green policies to Cameron. The YouGov poll suggests voters will have a mixed response if they became policy.

By 54% to 39%, people said they disagreed with the idea of making domestic flights and those to short-haul destinations in Europe more expensive by imposing Vat on them. They also rejected, by 70% to 22%, the notion of allowing councils to impose parking levies on out-of-town shopping centres.

But there was strong support, by 80% to 17%, for higher taxes on “gas guzzling” cars and lower ones on low-emission vehicles,a policy Brown appears likely to adopt. People also backed, by 83% to 13%, the proposal for lowering council tax and stamp duty on energy efficient homes.

The poll suggests politicians tread carefully on “green” taxes. By 83% to 9%, they think politicians use them as an excuse for raising the overall tax burden.

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