Currently, he is a citizen of the US.
Weather he is eligible to run for prez is still not determined, and will not be determined on these pages, although it does need to be addressed once and for all.
However, that is not why he fails to generate much interest other than on these same pages. His citizenship is pretty far down the list of his unfortunate negatives.
I think a lot, if not most, of the negatives are nonsense promoted by the Rubio camp.
In particular, Megan Kelly effectively apologized for using misleading video to try to paint Cruz as soft on immigration.
Sessions was very clear that Cruz was the person who killed the Gang of 8 -— yes, by using sneaky and underhanded methods -— but that is what it takes to destroy the RINOs that run the Senate.