While not a joke per se, this article was quite amusing in its way.
A few quotes:
Senator John McCain is so quick to pick up his gold-colored cellphone to solicit advice — from senators, campaign consultants, even the stray former deputy press secretary — that aides, concerned about his tendency to adopt the last opinion he has heard, have tried to cut back on the time he has to make calls.Mr. Schmidt has sought to cut down on Mr. McCain’s use of his cellphone and limit the people who have regular access to Mr. McCain in an effort to keep him more focused, advisers said. He has been the impetus for an effort by Mr. McCain to limit sharply his engagements with reporters, the kind of freewheeling encounters that Mr. McCain enjoys — and that helped him charm the news media for years — but that often lead him to veer from his campaign’s message of the day.
So essentially his own campaign is trying to ground McCain. It would be absolutely hilarious, but for the fact that this man might become the most powerful man in the world in a few months.