Both parents need to be U.S. citizens. Cruz is a good man. Cruz is ineligible.
Then lets see who's right?
U.S. law states that if only one parent was a U.S. citizen at the time of birth, that parent must have resided in the United States for at least ten years, at least five of which had to be after the age of 16. Cruz's mother meets this criteria, making him a “natural-born” citizen
As his mother was an American citizen, so it doesn't matter where he was born, he is still a “natural-born” citizen.
Ted Cruz for POTUS