A Poll for Libertarians

I ask this as a friend to better my own understanding and to learn from how you answer the question:
If it is the case that correct ideas tend to win out in a free market of ideas among rational people, why aren’t more people Libertarian?

a)    “The marketplace of ideas isn’t free.” Please tell me how so and what we are doing about it.
b)    “People aren’t intelligent or rational enough to understand Libertarianism.” But be careful: you may end up dismantle the entire premise of Libertarianism and open the door wide to a charge of hypocritical paternalism.
c)    “More people are Libertarian than you think. They just haven’t figured it out yet.” What prevents them figuring it out if it’s not a) or b)?
d)    “Correct ideas don’t win out in free markets.” Then what does and how can we make Libertarianism look a bit more like what does win out?
e)    “Gee, I guess that must mean that … Libertarianism isn’t correct.” If this one question was enough to shake your faith, you can’t have been very Libertarian to start with.
f)    “There’s another factor you haven’t included, and it’s ______________.”

If you aren’t Libertarian, feel free to answer for your own ideology. (Why aren’t more people Progressive?  Why aren’t more people Bolivarian socialists?) I direct this to Libertarians because they have the most axiomatic political belief system, a system that (as I understand it) is based largely on these assumptions, and I have an easier time imagining what some other systems would answer.