Uh, you might want to read up on that.
He would most certainly have to have SOMETHING to prove his US citizenship. Even his campaign knows that because they made a claim that his mother HAD applied for the CRBA so Cruz could have a US passport. THEY know it.
Cruz was born and a Canadian birth certificate was issued to his parents. That is not sufficient proof of eligibility for US citizenship. Read that link. That is the offical requirement from Canada, US consulate on how to secure the US citizenship document. I am not making this up.
I don’t need to read up on it. I already read the document at the link.
A CRBA is not required to get a U.S. passport and a U.S. passport is sufficient to document one’s citizenship.