All that is needed is for a court, any court to rule that way. But thus far the courts have ruled that Ted Cruz is a natural born citizen of the United States of America.
For example:
““Having extensively reviewed all articles cited in this opinion, as well as many others, this Court holds, consistent with the common law precedent and statutory history, that a ‘natural born citizen’ includes any person who is a United States citizen from birth,” wrote Judge Dan Pellegrini in a written opinion issued after denied the petition at a hearing Thursday.”
The Pennsylvania Supreme Court then affirmed Judge Pellegrini’s ruling.
This is not the first time that a court has ruled that red=white. We can only hope the Superior courts will actually refer to the Constitution and case law.