Vimes had once discussed the Ephebian idea of ‘democracy’ with Carrot, and had been rather interested in the idea that everyone had a vote until he found out that while he, Vimes, would have a vote, there was no way in the rules that anyone could prevent Nobby Nobbs from having one as well. Vimes could see the flaw there straight away.
-Terry Pratchett, The Fifth Elephant
He had such a way with words, he did.
This depend very much on how you define "fair," and how it is used in context.
So, I would say a system that only let's white male landowners vote is not "fair" because only an elite group gets to vote. But if their votes are counted properly, and their decision upheld, the election is "fair," and it's a democracy.
On the other hand, a system that lets everyone over 18 vote is arguably "fair." But if the votes are not counted correctly, and the results are false, then the election is not "fair," and you don't have a democracy.
To further the thought, I suppose that if the voting populating is a small enough percentage of the general populating, then it is not a democracy, rather than just a bad democracy. Not sure where that line is, though.