There is enough case law on citizens born in the US to make debate difficult. But the case law on citizens born abroad is a cinch. Well, for those who aren't deliberately obtuse, ignorant, or deliberately subversive.
There is consensus among academics that those born on American soil are natural born citizens, or jus soli, regardless of parental citizenship status.
In a 2008 article published by the Michigan Law Review, Lawrence Solum, Professor of Law at the University of Illinois, stated that “there is general agreement on the core of [the] meaning [of the Presidential Eligibility Clause]. Anyone born on American soil whose parents are citizens of the United States is a ‘natural born citizen’”. In April 2010, Solum republished the same article as an online draft, in which he clarified his original statement so that it would not be misunderstood as excluding the children of one citizen parent. In a footnote he explained, “based on my reading of the historical sources, there is no credible case that a person born on American soil with one American parent was clearly not a ‘natural born citizen’.” He further extended natural born citizenship to all cases of jus soli as the “conventional view”. Although Solum stated elsewhere that the two-citizen-parents arguments weren’t “crazy”, he believes “the much stronger argument suggests that if you were born on American soil that you would be considered a natural born citizen.”
Ronald Rotunda, Professor of Law at Chapman University, has remarked “There’s [sic] some people who say that both parents need to be citizens. That’s never been the law.”
Polly Price, Professor of Law at Emory University, has commented “It’s a little confusing, but most scholars think it’s a pretty unusual position for anyone to think the natural born citizen clause would exclude someone born in the U.S.”
Chin concurred with that assessment, stating, “there is agreement that ‘natural born citizens’ include those made citizens by birth under the 14th Amendment.”
Similarly, Eugene Volokh, Professor of Law at UCLA, found “quite persuasive” the reasoning employed by the Indiana Court of Appeals, which had concluded “that persons born within the borders of the United States are ‘natural born Citizens’ for Article II, Section 1 purposes, regardless of the citizenship of their parents”.
Daniel Tokaji, Professor of Law at Ohio State University, agrees the citizenship status of a U.S.-born candidate’s parents is irrelevant.