Both of their citizenships were recently under question - Barack born in Honolulu Hawaii to an American mother and a Kenyan father - to me, that's a US citizen.
But I know nothing of John McCain who was actually born in the Panama Canal Zone. For all I know, he could be an illegal Panamanian residing in the US, masquerading as an American.
:sarcasm: firmly set.
If you don't know your history about PCZ - you need to review it - it was a U.S. territory until, I believe, 1999.
ON EDIT. Interesting factoid here:
Almost from the inception of the Canal Zone, questions arose as to whether the Zone was considered part of the United States for constitutional purposes, or, in the phrase of the day, whether the Constitution followed the flag. On July 28, 1904, Controller of the Treasury Robert Tracewell stated, "While the general spirit and purpose of the Constitution is applicable to the zone, that domain is not a part of the United States within the full meaning of the Constitution and laws of the country.<4> In 1953, Congress passed legislation to specify the status of Americans born in the Canal Zone--and to exclude non-Americans born there from citizenship. Title 8, Section 1403 of the United States Code grants citizenship to those born in the Canal Zone with at least one parent who is a United States citizen. This differs from the provision in the Fourteenth Amendment which grants citizenship to all born in the United States, regardless of parental nationality.