Libertarian Democrats are like the 4th of July in England. It doesn't happen.
This is why I find labels to be stupid.
I don't agree with everything democrat or liberal, i don't agree with everything republican or conservative, I don't agree with everything libertarian, I don't agree with everything green, I don't agree with everything anything. I think all politicians are full of hogwash, and I've become jaded when it comes to the political system.
'Libertarian Democrats' might not happen...but there are people who might agree with some democrat ideas (and maybe oppose the libertarian viewpoint), while at the same time agreeing with some libertarian ideas (and opposing the democrat viewpoint). This is why I myself do not say that I am a 'Libertarian Democrat'...but rather that for most issues my ideas are generally close to either the democrat view, or the libertarian view. And then there are some ideas that I might even have a republican view.
Too often to me it seems that democrats uphold the democratic viewpoints simply because they call themself a democrat and so feel they need to support "their party". And if someone who calls themself a democrat goes against a democratic ideal on a certain issue, then "they are not a true democrat", or so says the masses. Same with the republican party.
I don't need labels to confine my beliefs to, and that is why I consider myself independent. I will make my own choice, it just so happens that in many circumstances my ideals, depending on the issue, generally fall along either democratic lines, or libertarian lines....with the rare swing to the republican side. And no one can tell me I'm wrong.