Most people would probably say that having free elections where everyone is allowed to run and everybody (Within reason) is allowed to vote and that each vote should count more or less the same.
I've been thinking a bit about this and I think there is one more thing missing from the list above and that is that you need to have more than one plausible choice. There has to be a working opposition. When a country has a working opposition that implies that power will need to transfer every once in a while between the different available choices.
Looking at it through those eyes the democratic countries of the world all of a sudden becomes a lot less. For instance Japan has definitely never had a working democracy. Although they might actually be joining the club with the upcoming election where for the first time ever the ruling party is looking like it will be voted out of power (Not counting a brief one year stint where the opposition was in power several decades ago). Most countries of Western Europe pass with flying colors.
One country which is dangerously close to failing this test though is the United States of America. On the local level it definitely has a great working democracy when it comes to electing public officials, almost to the point of it being stupid what an amazing amount of people have to run for their seats (Seriously why do you have elections for judges, would you not want the most qualified for that job instead of the most popular candidate). However on the national stage you have only two even plausible parties. Both of which is so ridiculously similar in their policies that it is very hard to tell them apart. For instance can someone explain the difference between a Fiscal Conservative Democrat and a Compassionate Conservative? I sure can't do it even though I like to think I am pretty interested in politics.
That's why it's so funny to me to look at US news outlets completely vilifying the "other side" even though to me they basically want exactly the same thing. I think this is also why news in the US has a tendency to get bogged down in such an amazing amount of inconsequential nonsense instead of actually reporting issues. There is really very little to report where it comes to issues because everybody in politics basically agrees on the big picture. It's also probably why the most stupid fringe issues have a tendency to take such a center stage in a lot of elections (Gay marriage, abortion and stem cell research springs to mind), simply because that's the only issues that the candidates disagree on.
It would be great if instead of Democrats and Republicans we could have a couple of more parties that actually had some beliefs except just getting elected. For instance it would be very easy to split the republicans into fiscal conservatives and moral conservatives. Same thing with the democrats it seems very easy to divide them into liberals (Not the US definition of the term, but as in following liberalist ideals) and socialists (The people now called left wing liberals here).
The problem with the US democracy is that every single seat is a winner take all contest which means that anything less than 50% will loose which means that for the foreseeable future until the US changes its constitution it will probably not have a great working democracy because everybody who wants to get elected have to place their feet firmly in the middle of the trough to have a chance and that's why it is so crowded there now here. I realize that there really isn't any way of getting around this issue for presidential (And governor elections as well). But for the legislative assemblies, especially the house of representatives I see no problem with having fractional elections from each state (They do it in the European Parliament).
I don't see this happening anytime soon, but one can always hope that at some point we could get a working democracy here in the United States too at some point.