Libertarians vote and likely vote in large numbers, they are typically well versed in the issues. What sort of fight did you have in mind? Milton Friedman described himself as a libertarian with a small “L” but voted Republican out of necessity. Most libertarians would probably describe themselves the same way.
The sole result of people voting libertarian (in the low single digit percentages, not exactly “large”) is that they make it so Republicans lose to Dems.
The LP agenda is described partially above, as it was posted on FR not long ago. The LP is the ultra ultra kook wingnut fringe of the left.