I think this video explains many of the problems with our voting system: http://www.youtube.com/watch?v=s7tWHJfhiyo
I think a democracy with a different voting system could work, but only in a country where the education system is extremely good. Since around 40% of Americans never graduate high school, and since most of our high schools don't actually teach very well anyways, ours would not be a good candidate.
But I don't know of any democracies that are not subject to the problems pointed out in that video.
Totalitarian systems certainly worked, but they were overthrown because the populations under their rule found it unbearable. But that does not mean that the first system we invented afterward is the best one. Our current system is a bit of an experiment, and it worked for a while but it seems to be hard to sustain over time. The government has trouble accomplishing much because when one party is elected it undoes everything done by the previous establishment. This makes it hard for our country to accomplish anything efficiently.
But what systems could we offer in place of what we have now? And how would a new system be put in place?
I find it hard to imagine any real change happening in the US until the economy or living conditions reach levels that a 'first world' country finds unacceptable. Otherwise people will remain mostly complacent and try to work within the system for change, which does not allow for something other than democracy.