You may as well stay home. Well, maybe you are a little better off voting 3rd party if you want that party to get federal dollars they need every vote they can get.
If you are in a swing state and you would prefer the Republicans over the Democrats, or visa versa, you're an idiot. You potentially cost Trump MI, AZ, GA, PA or MN.
If you are in a blue state and you are a con, then you are smart to vote 3rd party.
But if you lean left and you are voting 3rd party in a swing state, you're a jackass.
So it depends on which way you lean and what state you are in. Can you tell us? What state do you live in and do you lean left or right? I'll tell you if you are a dummy or not.