I suggest you read the U.S.Constitution Article I, Section 3:
“No person shall be a Senator who shall not have attained the Age of thirty Years, and been nine Years a Citizen of the United States, and who shall not, when elected, be an inhabitant of that State for which he shall be chosen.”
It says, “...nine years a Citizen of the United States...”.
Being a natural born Citizen is an eligibility requirement for the President.
And are you contending that Cruz has not been a U.S. citizen for at least nine years?