Vote even if it’s guaranteed to not change the outcome

If you want a say in this country, you need to vote, whether or not you are voting in a competitive race. Here’s why: politicians care only about the preferences of voters. If they know that you voted, they will care about not pissing you off. If you don’t, what you want will not matter to them.
I have spent my entire life, until this year, in deeply liberal places. With the exception of governor races, my state and district always elects Democrats. As someone who has tended to agree with Democratic policies, I was fine with that. I didn’t vote because I knew that my vote would have no impact on the outcome. Even if the overall elections didn’t always work out, I never ran the risk of my non-vote costing my preferred candidate the election.
As I have become more interested in the data side of politics, I realize there is another reason to vote that I have overlooked. In short, there is an industry built around measuring political preferences and participation. Every candidate has reams of reports that describe the preferences of voters, possible voters, and non-voters. These reports may say things like: “voters under 35 are really nervous about racking up a huge government deficit, which they will have to pay for later in life” as well as “voters under 35 do not vote as much as voters over 65.”
But what incentive does a candidate or politician have to care about the first statement given the second? None. The first statement doesn’t matter in a world where that preference is not going to be communicated via voting, especially if the opposite preference is held by people who are way more likely to actually vote on whether a candidate is elected or re-elected.
These numbers are from the 2012 presidential election, but only 46% of those under 35 voted.  (72% of those over 70 voted.) If that number was 50% instead of 46%, you can be damn sure that politicians in competitive races would be a lot more hesitant to favor policies that under 35s are nervous about. It’s that simple, it really is. If you are in a race where the difference is less than a thousand votes (many House races will be within this margin), pissing off under 35s could sink your campaign…but only if we show them that we are willing to vote.