[Mariner]

"Does Cruz possess a US Passport?"

Agreed. That would be proof of citizenship.

Would that be proof of NBC?

[Mariner]

http://www.fas.org/sgp/crs/misc/R42097.pdf

[Mariner]

The above Congressional Research Service Report indicates the issue of "NBC" is subject to some legitimate legal questions if the person is foreign born:

As discussed in more detail in the following section of this report, there have been some legitimate legal arguments and varying opinions about the status of foreign born children of U.S. citizens as being either “natural born” citizens under common law principles, or citizens who are “naturalized” by statute.

[AFret.]

No. Citizenship only..