From an attendee:

We heard that McCain folks bought 500 tickets or more for CPAC – so yes, they did pack the house which made sense given since they expected they were going into hostile territory given last year and they could not take any risks at this point. Also they raised expectations big time that conservatives would be unbelievably rude to them – which of course was easy to sell the media on – who always believe a McCain characterization of conservatives as the mean nasty sort. Obviously Mitt pulling out changed the dynamic of the room too. The fight was over. That combined with conservatives are more polite and nice than McCain or the media given them credit for along with good planning on Team McCain’s part explains the dynamic.

Again, nothing wrong with that. Just following up because the question was raised.