Who might replace Andy Coulson?

I think that Fraser Nelson in The Spectator may have unconsciously put his finger on a possible replcament:

'As the Cameroons are such West Wing junkies, here’s Leo McGarry trying to make up with his wife – but admitting that being Chief of Staff took precedence over everything else. He buys her a choker and dinner, to apologise for never being around. His wife packs and calls a taxi. She tells Leo:

“I don't want to live like this. I just can't....”
“This is the most important thing I'll ever do, Jenny. I have to do it well.”
“It's not more important than your marriage.”
“It is more important than my marriage, right now. These few years while I'm doing this, yes, it's more important than my marriage.”

Leo spoke the truth: this is the trade-off you make. Job first, life distant second. Who will make that trade-off for the great cause of the coalition? That – and the sheer pressures of the job – is why the vacancy is so hard to fill. '

A political operator who has a grudge against Ed Miliband & Ed Balls and already has marital issues... how about Alan Johnson?