-Title 8 of the U.S. Code fills in the gaps left by the Constitution. Section 1401 defines the following as people who are "citizens of the United States at birth:"

* Anyone born inside the United States *
* Any Indian or Eskimo born in the United States, provided being a citizen of the U.S. does not impair the person's status as a citizen of the tribe
* Any one born outside the United States, both of whose parents are citizens of the U.S., as long as one parent has lived in the U.S.
* Any one born outside the United States, if one parent is a citizen and lived in the U.S. for at least one year and the other parent is a U.S. national
* Any one born in a U.S. possession, if one parent is a citizen and lived in the U.S. for at least one year
* Any one found in the U.S. under the age of five, whose parentage cannot be determined, as long as proof of non-citizenship is not provided by age 21
* Any one born outside the United States, if one parent is an alien and as long as the other parent is a citizen of the U.S. who lived in the U.S. for at least five years (with military and diplomatic service included in this time)
* A final, historical condition: a person born before 5/24/1934 of an alien father and a U.S. citizen mother who has lived in the U.S.

From here.

But personally I'd be absolutely fine with McCain being disqualified for the Presidency.