Even if you're in a "safe" state for Clinton, I'd urge you to vote for her just to run up the numbers. Trump is going to whine and cry when he loses, and his supporters will be all butt-hurt and ready to call it rigged unless it's a true blowout. I, like your son (I could probably be your father), was avidly supporting Bernie's run and have little love for the Clintons. But someone is going to appoint justices to the SCOTUS, and I know what kind of company Cheeto-face keeps.
The last thing you need is Hillary thinking she has a crystal clear and fully supported mandate to do whatever she wants. The last thing you want to tell her is that you want her to be President, rather than you are making her President because the other choice is worse. Remember, this is Hillary Clinton, corporate big money insider stooge.