It mediocre, but... well... meh.
I didn't think there was any problem with the use of parenthesis.
As far as the rant about DIEBOLD, it needs to be tied into the rest of the essay better, and calling Ohio a "hardend blue state" is an exaggeration. Also on the matter of facts, if your doing any kind of semi-serious writing, you really need to cross refernce anything you find on wikipedia with another source (not that I think your understanding of the affair in chile is incorrect, at least not from what i've read)
The Conclusion that you come to is also rather weak, not much more than "OMG capitalism is bizaro socialism!". You do add something in your description of how the government and corporations have been working together (I think Ralph Nader wrote a book about this, something along the lines of "Corporate Welfare", but I don't remember right now), but that should not be a surprise because, as any socialist should relize, corporations, governments, and organized religions are all power structures, just by different names, and different (but fluid) expectations of power and democracy. The less a government is "of, for, and by the people" (which is where I think you were going with the voting fraud stuff), in other words an oligarchy, its obvious it will do what is best for the leaders, which includes allying with other oligarchies (corporations) to rob the prolitariat. [I went off on a tangent here, you can skip the rest of this paragraph] This is why I have always been annoyed by people who call socialism naive, because to me it seems as stupid to trust corporations as totalitarian governments (I dont mean to sound overly dramatic, of course corporations do not have the same power as a government, but they can, and in the US have, been moving closer to this), and a much better idea to have things controled by the people (as the government). In the later case I suppose the effectiveness of such a government would be based on the ability of the people elect leaders that are not stupid or despotic, and would undo reforms. Not that there necisarily have to be leaders, at least not as normaly would think of them, but now I've realy gone off topic.
It would also be nice if you could define what you mean by libertarian for the benefit of americans, because here the term almost universily denotes neoliberalism, a conotation that I understand it dose not have in the rest of the world.
Also, footnotes > endnotes
This post realy got off its original point, and I apologize for that.