Re: "You can trust US", says Uncle Sam - yeah, right!
http://mic.com/articles/87719/princeton-concludes-what-kind-of-government-america-really-has-and-it-s-not-a-democracy is an interesting (albeit badly flawed) article. Certainly I believe that the USA is indeed an oligarchy, much as (classical) Rome was in the decades before the civil war (when it ws nominally a republic). But that article is more likely to weaken my belief than strengthen it. It's a great pity you chose to reference that junk, looper.
But the graph showing that the 20th percentile was often above the median, although good for a laugh, is a pretty appalling piece of nonsense - no-one with any sort of mathematical literacy could believe that it was even remotely near being accurate. It destroyed my ability to believe anything in the article was reliable.
Of course the absence of democracy problem isn't restricted to the USA; the UK, Spain, France, Germany, Italy, Belgium and the Netherlands are all oligarchies or something else distinctly non-democratic too. I don't know the rest of Europe well enough to state for certain that nealy all the remaining European countries are either dictatorships or oligarchies too, but I'm pretty sure the vast majority are. So is India, from what I've seen of it, in fact I don't believe there is a real democracy anywhere on earth - except maybe Switzerland.