You are right McCain was born in the Canal Zone (A US Territory) to US Citizens, but Obama was born in the US as a citizen of his father's nation, the United Kingdom. This made Obama ineligible for citizenship in the US.<quoted text>
McCain’s Constitutional Dilemma: Native Son But Not Natural Born?
February 29, 2008 / http://tinyurl.com/2am7hd
John McCain’s possible election could trigger review under an obscure part of the Constitution: the birth eligibility provision of Article II. The requirement that an American be “natural-born” has long been controversial, but few associated John McCain with the problem as opposed to other leaders like Arnold Schwarzenegger. McCain, however, may be a foreign born citizen given his birth in the Canal Zone. Due to the bar on advisory opinions, this issue might not be ripe for review until after the general election, triggering another Bush v. Gore moment in the high court. Ted Olson has even been retained for the possible fight to complete the scene for a Supreme redux.
McCain was born in 1936 in the Panama Canal Zone while his father was stationed there as a naval officer. In 1787, however, the framers insisted that any president be natural born — that is, born within the United States. It is a requirement that some of us have long criticized as counter to our tradition as a nation of immigrants
Jonathan Turley Constitutional Law
Has Obama ever been naturalized, I don't think so, this would mean we have an alien sitting in the White House.