The initial Cameron impact has been about three points for the Tories. The latest Populus poll for The Times still gives Labour a narrow lead over the Tories, of 38 to 35 per cent (against 40 to 32 per cent a month ago), with the Liberal Democrats unchanged on 19 per cent. This is in contrast with the small Tory leads shown by ICM and YouGov. The Populus poll was carried out between Friday and Sunday, later than the other two, so the immediate euphoria may have worn off. Nonetheless, the main parties’ ratings are within the margin of error.

By contrast, this was half the jump in Labour’s rating in summer 1994 when Tony Blair became leader, although his party was already between 10 and 20 points ahead in the polls.

The key point is that the Tories look competitive again. This is underlined by questions looking ahead to the next election. When voters are asked which party they would back then on the assumption that Labour is led by Gordon Brown, a Cameron-led Tory party is ahead at 41 per cent to Labour on 35 per cent (against 35 to 37 per cent a month ago). But given the way that votes are distributed, the Tories would not necessarily win an overall majority, as opposed to a hung Parliament.

Mr Cameron and Mr Brown run level-pegging, at 37 to 36 per cent, as the preferred choice of prime minister after the next election. The new Tory leader is ahead among professionals and managers, capturing some of the support that Mr Blair has had. But Mr Cameron does better among Tory voters (83 per cent) than Mr Brown does among Labour supporters (68 per cent).

For a long time, the Tories have lagged well behind Labour and the Liberal Democrats on all measures of party attributes. The overall picture has not altered much. There has been no change since September in the numbers thinking that the Tories care about the problems of ordinary people and are honest and principled (both 34 per cent).

By contrast, there has been a sharp rise in the number thinking that the Tories have a strong team of leaders (up 14 at 36 per cent) and are united (up 11 at 39 per cent), a tribute to Mr Cameron’s two-to-one victory. This amounts to an opportunity for the Tories, no more. What voters are saying is: “We like what we see. Labour looks shopsoiled and David Cameron is saying the right things, but we are not willing to commit ourselves fully until we can be sure that the Tories have really changed.”

For Mr Cameron, it is crucial that the Tories are, at long last, enjoying the same ratings as Labour. That should give him breathing space. If Mr Cameron can credibly offer the hope of victory, then he should be able to overcome any internal opposition.

Populus interviewed a random sample of 1,521 adults aged over 18 by telephone between December 9 and 11. Interviews were conducted across the country and have been weighted to be representative of all adults. Populus is a member of the British Polling Council and abides by its rules. For more details: see www.populuslimited.com

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