In 2008 the Senate asked Lawrence Tribe and Ted Olson for their opinion on McCain's eligibility. Here is what they said suggesting that either jus sanguinis or jus solis could confer NBC.
Per request from Senator McCain two researchers presented a report on March 19, 2008, declaring McCain to be eligible.
The Constitution does not define the meaning of “natural born Citizen.” The U.S. Supreme Court gives meaning to terms that are not expressly defined in the Constitution by looking to the context in which those terms are used; to statutes enacted by the First Congress, Marsh v. Chambers, 463 U.S. 783, 790-91 (1983); and to the common law at the time of the Founding. United Suites v. Wong Kim Ark, 169 U.S. 649, 655 (1898). These sources all confirm that the phrase “natural born” includes both birth abroad to parents who were citizens, and birth within a nation’s territory and allegiance. Thus, regardless of the sovereign status of the Panama Canal Zone at the time of Senator McCain’s birth, he is a “natural born” citizen because he was born to parents who were U.S. citizens.
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Indeed, the statute that the First Congress enacted on this subject not only established that such children are U.S. citizens, but also expressly referred to them as “natural born citizens.” Act of Mar. 26, 1790, ch. 3, § 1, 1 Stat. 103, 104.
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Historical practice confirms that birth on soil that is under the sovereignty of the United States, but not within a State, satisfies the Natural Born Citizen Clause. For example, Vice President Charles Curtis was born in the territory of Kansas on January 25, 1860 — one year before Kansas became a State. Because the Twelfth Amendment requires that Vice Presidents possess the same qualifications as Presidents, the service of Vice President Curtis verifies that the phrase “natural born Citizen” includes birth outside of any State but within U.S. territory. Similarly, Senator Barry Goldwater was born in Arizona before its statehood, yet attained the Republican Party’s presidential nomination in 1964. And Senator Barack Obama was born in Hawaii on August 4, 1961 — not long after its admission to the Union on August 21, 1959. We find it inconceivable that Senator Obama would have been ineligible for the Presidency had he been born two years earlier.
Whether one agrees or disagrees with the opinion above is really irrelevant. This must be adjudicated in the courts sooner rather than later. We have 300,000 to 400,000 anchor babies born to illegal aliens every year. Today, one in 8 residents of this country is foreign born, the highest it has been in 90 years and by 2050 one in 5 will be foreign born. It is urgent that we resolve this matter.
Well the anchor baby question will have to be addressed through an interpretation of the 14th ammendment.
The NBC question was last addressed by the SCOTUS in about 1870. Minor vs Happersett identified natural born citizens as born in the US of two US citizens. I personally think the SCOTUS will have to address the question again and make a final interpretation to clear the matter up. They are trying to avoid it so who knows when it will be resolved. More and more states are challenging Barack Obamam’s eligibility so one of those cases may make it to the SCOTUS.