Over on PoliticalBetting Mike Smithson is giving much consideration to the surprising ease with which Cameron is shifting to the centre without losing much core support. 96% of voters who voted Tory at the last election still plan to vote Tory again, 1 in 9 who voted Labour plan to vote Tory and 1/8 who voted LibDem plan to vote Tory.

So despite the whining on ConservativeHome and in the Telegraph, Tories are sticking with Dave and he is winning over LibDem and Labour voters. Even after moves like this week’s air-travel-tax debacle, which was very badly spun and has resulted in a lot of unease in the ranks and some backtracking – “were just throwing out ideas”, “it is a proposal for discussion” they say now.

Guido hears that Dave even called Will Lewis, editor of the Telegraph to remonstrate about his coverage of the proposal; “Why are you being so horribly harsh about this air-tax” Dave complained, “Well most of our readers have second homes or enjoy foreign holidays, what do you expect me to do?” came the reply.

Nevertheless, Tory voters will it seems just gnash their teeth and still vote for him. They have nowhere elese to go…