The Conservatives are level with Labour in this week’s Ashcroft National Poll conducted over the past turbulent weekend. Other surveys published in recent days have shown no consistent pattern; Labour leads with other pollsters have been up, down and unchanged. In the ANP both main parties remain within the margin of error of their long term average: 30 per cent for the Tories, 34 per cent for Labour.

One third (33 per cent) of voters said they were satisfied with the job David Cameron was doing overall as Prime Minister, up four points since I last asked the question in May.

Nearly three in ten said they were dissatisfied but would still rather have him as PM than Ed Miliband (29 per cent, down one point since May). Only just over a quarter (26 per cent, down two points) said they would prefer to see Miliband in Number Ten.

Swing voters, who say they do not know how they will vote or that they may switch from their current party, were more likely than average to say they preferred Cameron (69 per cent). Only two thirds of Labour voters (65 per cent) said they would rather see Miliband as PM. The remaining third who are either satisfied with Cameron (16 per cent) or dissatisfied but think he is better than their own leader (16 per cent); whether this will be enough to persuade them to switch parties as the election approaches is a different question.

The Liberal Democrats, preparing for their own conference next week, need to persuade voters that they have had a positive influence on the decisions of the government and deserve to be back in office.

This looks like an uphill struggle. Only one third (33 per cent) said they thought the Lib Dems had had the right amount of influence within the coalition, while four in ten (including 42 per cent of swing voters) thought they did not seem to have enough influence. As I have found in other research, many people are glad they are there to temper the worst instincts of the Tories, but they struggle to name specific Lib Dem achievements.

The Conservatives, meanwhile, should not assume most people share their own understandable view that the government would have achieved more and better things without the yellow shackles. Though Tory voters were more likely than most to think the Lib Dems have had too much influence (26 per cent), even they were more inclined to think Nick Clegg’s party had either had the right amount of influence (51 per cent) or too little (21 per cent).

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