Santorum is a religious right nut job.
That's where his conservative cred ends.
Paul is the most conservative.
What is conservative?
To me libertarianism is more of a true conservatism while the social conservatism of the South is just our version of the Islamists in the middle east.
I don't personally consder that conservative at all but more religious statist.
Santorum is more a religious statist to me
Paul is more a conservative
Paul is no friken conservative, he is conservative on domestic policies but is foregn policies are far to the left of Obama, So it's a wash. Santorum probably the most conservative