Down the road, (20-30 years), I think the Libertarian party has a chance of taking hold as these Paul supporters grow up.. (assuming some of them want to have kids of course)
The chances of the Libertarian Party are like the chances of seeing the advent of controlled nuclear fusion: always 20-30 years away.
Libertarianism is, at root, about an ideology rather than practical methods of governance. And the problem with the Libertarian Party is that "growing up" inevitably involves acknowledging a thing or two about reality, including about human nature and what it means to live among people with different ideas and opinions. And thus grown-ups tend no longer to be "libertarians" in any sense that could support a political party.
There are libertarians who are adults, in the biological sense of the term. And some of them are even grown-ups. However, I've found in debates with libertarians that when the debate gets down to brass tacks, one often (not always, but often), sees the libertarians go ad hominem rather quickly ... which suggests that they find "grown-up" to be an elusive trait.