"The Conservative Shadow Home Secretary, David Davis, has resigned as an MP in order to fight a by-election in his constituency on the issue of 42 days. Which of these statements comes closer to your view?

He is doing it mainly as a genuine act of principle in order to defend civil liberties: 29%

He is doing it mainly as a cynical ploy to help the Conservative Party and his own career: 41%

Don’t know: 30%"

The poll finds that the overall Tory lead is 22%, 47% to 25%.  More in this PDF.