I vote as a Californian. You’ll have to work a little harder to convince me that my sitting out the election will give California to the Republicans.
In 2012, the results were 7,854,285 (60.24%) D, and 4,839,958 R (37.12%).
If the numbers are at all similar, my little protest would have to be joined by 3,000,000 other people, or 17% of the registered voters in the state (by 2015 numbers), and nearly 25% of the voters who actually turned out for the election; if my math is right, that would be 40% of the Democrats.
In the unlikely event that 40% of the party’s voters sit out the general election because they don’t like the candidate, the other party deserves to win. But I think my little protest will be consequence-free.