Senator Marco Rubio's father was not a naturalized citizen when Marco was born in May 1971 per National Archives data. His father applied for naturalization in Sep 1975
By CDR Kerchner
May 22, 2011
A natural born Citizen of the United States is one born in the United States to two U.S. Citizens who were Citizens of the United States either by birth or naturalization at the time of the birth of the child. A natural born Citizen of the United States is a child born with sole allegiance to the United States, a person born without Citizenship in any other country other than the USA at the time of their birth. A natural born Citizen has no foreign influence or claim on them by another country at the time of their birth under U.S. law and the Law of Nations. That is why the founders and framers chose the legal term of art “natural born Citizen” for the eligibility clause for the singular most power office in our form of government, the President and Commander in Chief of our military. They did not wish command of our military forces to ever devolve to a person born with dual allegiances.