Natelson is correct that I (and others) may have been too quick to suggest that this issue is completely settled. The historical materials are not as clear as one might like. Nonetheless, I think that Ramsey’s account provides the best understanding of the meaning of “natural born citizen,” and that this account is also the most consistent with historical practice. Plausible arguments can be made to the contrary, but they are anything but conclusive.
While the Supreme Court has not weighed in on the issue, Cruz is not the first person to run for president who was born outside of the United States. Several prior candidates were born in U.S. territories, rather than states (including McCain and Sen. Barry Goldwater), and George Romney ran for president in 1968 despite having been born in Mexico. For these reasons, I would be quite surprised were a court to conclude that Cruz is ineligible. Whether Cruz is qualified to be president is a question for voters to decide.
I’d also point readers to Derek Muller’s analysis of the difficult question of if/how such a question could end up in court.