Ichkeria....Staying in the EU was Tory Party policy, as it was the policy of most other political Partys.
So how could Cameron have campaigned for anything else ? The current Tory PM, Mrs May also campaigned for the same cause, as did most other Tory MPs.
I would have had less respect for him if he gone against his better judgement, and the polices of his own Party, by campaigning to leave.
This link makes interesting reading :::
http://www.bbc.co.uk/news/uk-politics-eu-referendum-35616946
479 MPs voted to remain, against 158 to leave. Its clear that Cameron wasn't the only one that wanted to stay. We haven't had an Election since June 23rd, so we must assume that all the MPs broadly still think the way they did on June 22nd....ie the vast majority still don't want to leave.