Ed Miliband's speech to Labour's conference has boosted his and the party's ratings.

YouGov's first survey since Miliband delivered his 'one nation' speech on Tuesday shows Labour's lead up to 14 points, matching its highest this year and following leads of 5 and 9 points in our two previous polls. The voting figures - Labour 45%, Conservative 31%, Lib Dem 10%, - are close to our six-month average of 43 / 33 / 9. On their own, our latest figures could reflect nothing more than sampling fluctuation. However, other data suggests that the bounce is real.

For example, Miliband has climbed to his highest figure when people are asked who would make the best Prime Minister. With 27%, he remains behind David Cameron, 31%. However, Cameron's 4-point lead is his lowest since Miliband became party leader, and compares with the 9-10 point lead that Cameron has generally enjoyed in recent months.

We also repeated a series of questions about Miliband that we asked last week. Here are the main findings:

As those figures show, Miliband remains in negative territory on each issue, but by significantly less than last week. And the fact that the biggest jump, of 12 points, relates to making it clear what he stands for suggests that his 'one nation' message has made an impact.

This is confirmed by responses to another question. We asked: 'Some people talk about building 'one nation', meaning a Britain in which there is a shared national purpose and people come together to tackle shared problems. Which, if any, of these political parties best fits the description of 'one nation' party?'

Twice as many people said Labour (28%) than Conservative (14%), even though 'one nation' has historically been a Conservative concept. It flows from Benjamin Disraeli's observation more than 160 years ago that Britons were divided into 'two nations, between whom there is no intercourse and no sympathy'. Just 6% said Liberal Democrat. However, half the sample said either 'none of them' (39%) or don't know (13%). Labour may hold an advantage in the battle to claim the 'one nation' banner, but the war is far from over.

Overall, Miliband has done far better than last year, when there was no conference bounce. It remains to be seen whether his improved figures will persist. Conference bounces generally subside. But Miliband badly needed a good conference, and these results show he has reached his immediate goal.

See the full survey details and results here

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