Well, McCain suspended his campaign for several days and cancelled all his ads in Florida during part of the financial crisis. Obama’s team bought up most the ads.
Somehow,I don’t think Trump will pull a McCain. I also don’t see him whimpering about Hillary as Romney did about Obama.
I’m convinced that Romney threw the race on purpose.
Now that you mention McCain ‘suspending’ his campaign, it is fairly obvious that he threw his campaign too.