In the wake of recent polls  showing that the next election is now likely to produce a hung parliament, the Conservatives have been comforted by David Cameron's personal ratings, which have remained robust. British politics are becoming increasingly presidential, making the Tories confident they will win out.
But now a new PoliticsHome poll  has shown a significant fall in Cameron's approval rating in the past two months. On 18 September, his leadership approval score stood at +36, but by 27 November it had fallen to +21. The Tory leader's 17-point lead over Nick Clegg has been reduced to 7 points.
Significantly, the fall in support for Cameron is not tied to a general shift against the party leaders. Over the same period, Gordon Brown's approval rating has risen from -55 to (a still dismal) -46.
Perhaps the Tories need not worrry: Cameron retains a convincing lead over the PM. But the poll reinforces the sense that suddenly, for a number of reasons , the public is re-examining its views on both Cameron and his party. Those who complacently suggested  only a fortnight ago that Cameron was "closing the deal" will have to re-examine their assumptions, too.