Paul *IS* a Libertarian, though he runs on the republican ticket, if I'm not mistaken. His last run for President was on the Libertarian ticket, and his supporters are all Libertarians. His son, the Senator from Tennessee, Mr. Rand Paul, is a Libertarian. I love Libertarians, and I think we could do far worse than having one for President, but Dr. Paul is not the one. Rand maybe.
Ron and Rand Paul are small "l" libertarians within the Republican Party. Rand has never been anything other than a Republican.
Ron Paul only ran for President as a Libertarian back in 1988 because after having been part of a Republican Congress with a Republican president that still kept expanding the size of government, he had given up on the idea of the Republicans ever cutting the size of government.
Personally, I think that Ron Paul is not only the best choice -- he is the only choice for a presidential candidate who will actually do what he says he is going to do about cutting the size of government.
I think that Rand Paul would make an excellent VP.