Perhaps, but whomever runs second in the primary race has a shot at the vice position. Who knows.
Cruz would capture conservatives, some Hispanic (Cuban community for sure), portion of republicans.
Rand would capture some republicans, conservatives, libertarians and a portion of the moderate democrats.
Rand Paul is more conservative than libertarian, his father was opposite...more libertarian.
We gotta long way to go yet.
I also suspect that you are giving Rand more possible voters than there are/could be.