Unlike most other forms of government, democracy places special emphasis on citizens, who are believed to take responsibility for their government. Behind the platitudes, however, there are interesting philosophical issues. Here's an example:
There are at least two candidates running for President: Candidate C and Candidate T. These ones get the attention, and each tries to convince people to vote for them. Now, if Citizen X decides to vote for Candidate S instead, is it appropriate to say that they are responsible for either C or T being elected?

The first assumption is that not voting is not an option. Yet there are options other than C or T, Let's call these Candidates S and J.
One way to argue that X voting S or T is wrong is to say, for example, that Citizen X caused Candidate T to be elected by voting for Candidate S. This is clearly not the case, though, since X's vote was not registered for Candidate T, and registered votes are what cause candidates to be elected (at least ideally). What's more, to say that Citizen X's vote is what caused the election of Candidate T is to unfairly single out that one vote. Even in the impossibly rare situation where the votes between T and C were completely tied, save for one vote, there is no good reason to say that X's vote, registered at the same time as all of the others, was the one vote -- that little Yopp -- that sent C or T over the edge.
This naive view is not normally maintained. Rather, people say that X's vote permitted T to be elected. An analogy might be this: If X were to let their dog loose, and it bit a neighbor, then although X didn't cause the dog to bite the neighbor, X shouldn't have allowed that to happen.

--Tadd Ruetenik