Mara Liasson, writing for NPR on what matters in the election.
Also, while the electorate continues to get younger, browner and more female, a lot of those voters live in the wrong states as far as Democratic hopes at winning go. In other words, it doesn't matter as much if there's a huge surge in turnout in California and New York (two states where Hillary Clinton got one-fifth of all her votes from); it matters who shows up in Michigan, Pennsylvania and Wisconsin. In Michigan and Pennsylvania, white, working-class voters make up 56% of eligible voters; in Wisconsin, it's 61%.
I'm less interested in a candidate's national numbers than I am in their state-by-state numbers and how their positions poll in each battleground state. You can run up the score quite a bit in California and New York and still lose because voters in Pennsylvania don't like your plan to ban fracking and because white moderates in Wisconsin think your policies too radical.