Poor John McCain. As a politician he is stiff and erratic. He overplays bad hands and repeatedly injures himself with overreaching attacks. His debate skills are nonexistent.
McCain's SNL skits prove he does, however, have pretty fair comic timing. From a political point of view it was a waste of time. The SNL audience consists of stoned out kids and unreconstructed liberal hippies. There is nary a vote to be had there for an elderly Republican. I can think of a couple hundred better ways to spend a Saturday night three and half days before the election than hanging out in Manhatten. Sleep comes to mind.
Mostly the appearance proves that McCain missed his calling. With just a little work McCain could be a successful comedian, the new George Burns. Instead he has chosen to be a politican, a joke of a different kind.