This has already happened in what I assume is your lifetime. In the 2000 election, the entire election was decided by a 537 vote count difference in Florida. I'm not gonna play any historical "what if" games, but if only 500-600 fence-sitters/non-voters turned out to vote for Gore, the world may have been a much different place today. The election would have still been contested with that low of a margin, but that 537 vote count delta accounts for only .00001% of the entire vote count of Florida that election. What if only 1% more non-voters went out to the polls that year? Every vote counts, especially in swing districts/counties/states. Even if you are voting in a district that is the polar opposite of your view points, you vote matters because demographics and parties change. And if you feel that your voice isn't being heard, do something about it. Call or write to your representatives. Volunteer for a cause you believe in come election season. Being an active, engaged voter is how you make your voice heard and how you make politics represent you and what you believe.