One interesting thing is that some view Paul as among the most conservative candidates, while others (myself included) see him as among the most liberal Republicans. To me, libertarian beliefs consist of siding with the left (on stuff like drugs and national security), while others think they are conservative.
The reason I think he's among the most conservative is because he's using conservative ideas and conservative arguments to justify his position. Him being "soft on drugs" or whatever is both fiscally conservative (spending less money on criminal justice system) and would shrink government. Likewise, a smarter foreign policy would spend less and shrink government intervention when its not needed. The left wing has an entirely different worldview on these things even though they may be similar in position.