Ted Cruz and Rand Paul both oppose mass government surveillance and want the government to get a warrant - just as our constitution dictates.
Rand Paul, however, has dropped out of the race.
Many of the other candidates have the same stance on this as Rubio - Christie, Bush, Kasich, and I believe (but I don't know 100%) Carson as well. Not sure where Carly Fiorina stands on it, I hear so very little about her because she doesn't tell advertisements on the networks the way Trump does.
If this issue is important to you, then there's really only one candidate left who is on the side of privacy - and that is really, really sad. It should be all of them.