By Peter Hoskin
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Andrew CooperSteve
Hilton, James O’Shaughnessy, Tim Chatwin and, more recently, Rohan
. And now Andrew Cooper’s name can be added to the list of senior
advisers to have departed from David Cameron’s side. According to today’s Mail
on Sunday
, Mr Cooper, who was appointed Director of Government Strategy in
2011, is returning to the polling company that he helped found. He will, it's said, continue to do a bit of work for the Tory party.

why? And why now? The MoS puts it down to the presence of Lynton Crosby in
No.10. As one source tells the paper, “There was never going to be room for
both Andrew and Lynton” – and it’s a sentiment that I’ve heard from my own
sources plenty of times before. The idea is that the modernising Mr Cooper and
the blunter Mr Crosby were rubbing up badly against each other. Friction

so, there’s a bitter sort of irony to it – as the political distances between
the two men have probably closed in recent months. Not only is Mr Crosby more
broad-based than the reports would have you believe, but Mr Cooper has become
more hard-headed in Government. Sure, he is still, happily, a proponent of policies
such as gay marriage, and he’s still the man who once branded the Tories the “nasty
. But, thanks largely to his own polling, he’s rounded out his
modernisation for the times. He was one of the main
– philosophically, if not literally – of David Cameron’s last
conference speech, with its emphasis on aspiration and economic security. And he
has also urged tougher rhetoric on crime and welfare.

Cooper’s departure is rather embarrassing for Mr Cameron, coming, as it does,
on the back of all the other departures and of fairly
recent denials
that the pollster would quit. But the Prime Minister shouldn’t
dwell on that, nor on the working relationship between Messrs Cooper and
Crosby, whatever the truth of it. Instead, he should wonder about the systemic
problems that might be driving his staff away. It could well be that, as Lord
Ashcroft has warned,
there are too many people treading over the same ground with no-one in charge
of the overall choreography. Who really has been running government strategy?
Cooper? Crosby? George Osborne? All of them? None of them? It’s sometimes
difficult to tell.

Mr Cameron doesn’t answer such questions, then it’s likely that he’ll keep
shedding staff – and find them increasingly difficult to replace. Thanks to the
efforts of Andrew Cooper, and of Stephen Gilbert, No.10 now has a sophisticated
polling mechanism in place. But it’s the sort of machinery that requires operators.

Update, 2.30pm: The Spectator's James Forsyth, who also happens to be a Mail on Sunday columnist, has just quoted a No.10 source denying the Mail on Sunday's Andrew Cooper story. James's tweet reads as follows:

"Andrew Cooper is not leaving N0 10 according to a senior Downing Street source May go back to Populus at some point but ‘no plans’ at the mo"

To my eyes, though, the admission that Mr Cooper "may go back to Populus at some point but ‘no plans’ at the mo" is significant. There have been rumours for some time that the pollster would return to his polling company – so it could be that the Mail on Sunday were on to something with their original story, and Downing St are now trying to muddy the particulars.