Don't forget that the Democratic party has something called Super Delegates, which basically blocks any candidate they don't agree with, even if the candidate won the popular vote. If Trump ran as Democrat, he wouldn't be president today due to this.
Also, we shouldn't forget that Michael Bloomberg decided to run last-minute as a Democrat, with the Democrat party changing the applicant rules so that he could specifically run.
The whole political apparatus is entirely corrupt. I'm not sure voting helps at this point. We have a massive amount of people who are on the last of their savings, with no unemployment benefit coming their way to help out. This may be the beginning of a revolution, if people are angry enough, maybe.