Others disputed that McCain was born on a base, saying the hospital was in the CZ, but not on the base. Others felt like the entire Canal Zone, in the period in question would qualify as US Territory.
As he didn't win we never had to argue about it too much.
His BC, actually both long and short forms, has been posted here many times, it says he was born in Colon, Panama, which is neither on a US base, nor in the Canal Zone. But since he was born of two US Parents, he's natural born by all but the definition(s) that requires the birth be on US soil.
But that doesn't conform with the Common law definition in use at the time the Constitution was written. It also does not conform with the general practice of most nations *other than England* at the time, which went strictly by the parent's citizenship, regardless of birth location, and in "split" cases, by the father's citizenship. The English were more "liberal" and also made anyone born "in the realm" a natural born subject, with a few exceptions such as the children of ambassadors or of an occupying military force. That's per "Blackstone's Commentaries on the Laws of England". (Blackstone makes note of the difference between English and French practice in this regard).
You said — “As he didn’t win we never had to argue about it too much.”
If McCain were to be an alternative in case the other “ticket” can’t serve (as he was one of the candidates actually running) — then what is not an issue becomes an issue...
So, it would appear that McCain needs to be investigated as thoroughly as Obama, just in case McCain is the only other alternative.