Cameron’s strategy is a media strategy.
The media objects to a politician talking about immigration or Europe. Portillo for example writes in the ST over and over that the Party must fight on the middle ground and only mention the main issues that concern the public – health and education.
Whether the public cares about immigration or not (of course it does) the media will attack any politician who campaigns on it.
Europe meanwhile only has to silence opposition to become a fact of life.
The BBC backs Europe. Murdoch backs Europe. The Mail backs Brown who backs Europe. The guardian/observer back europe. There is little media left after that.
Cameron is known not to be euro-enthusiastic which is why he gets slammed in the murdoch press. If he opened up on Brussels with all Tory guns blazing, he would be shot down in flames as was Thatcher, IDS before him.
He has to tread warily around the media. Not to mention Ken Clarke and William Hague, who is as keen on the EU as anyone, the charming old fool.