We know that one vote rarely makes a difference. Common sense says as much. Honestly, how often in our nation's history has one vote really mattered? Not very, if at all. And there are great temptations not to vote, not the least of which are that a given election may be a foregone conclusion. They aren't necessarily; can you say Thomas Dewey?
Then there's the idea that it is a good and necessary thing to exercise your rights, even when they seem unneeded or, perhaps, pointless. You're exercising your rights when you walk into the restaurant of your choice, aren't you, when that choice really isn't particularly important, is it? No one would tell you that it's okay not to eat there that basis. But at the heart of it, that choice is a reflection of a very important right. Why treat your vote as less important?
And as always, there's the ages old saw about what if everyone thought like you? What if everyone quit voting because their single little tally meant relatively little? We shouldn't have to finish that thought. You know where it goes and we know how trite it sounds. Still, if you don't use your rights well someone will use them for you. You will get the government you deserve.
So vote, even if it doesn't mean much. The practical implications will certainly be small. The symbolic implications, however, will be a great victory for the individual.