Forget 1 in 10 million. For my state (Texas), a simple binomial model suggests my chance of being the critical vote is about 1 in 10^51121. I did vote, but it wasn't due to a instrumental pursuit of expected value. For me, it was an intrinsic value of civic participation and a feeling of connection with the political struggles of past generations. These things are part of my notion of the good life. If they're not part of yours, that's fine.