anyone running third-party is going to act as a spoiler and not much else. johnson is probably going to take votes from both of them, but i imagine more so from Annoying Orange than clinton. this running mate actually makes sense though, a sensible moderate from a strategic state to balance the ticket. that's exactly what you would expect from an establishment politician. Annoying Orange for some reason chose a tea party republican, which seems like a strange move considering he likely already had the far right vote
also ipquarx is correct about bernie's endorsement. it's just political nonsense because bernie would much rather have any democrat in office than any republican. running third party would pretty much guarantee a Annoying Orange presidency and he knows that because he isn't stupid. regardless of how much he actually supports clinton, the entire point is to make a statement to his supporters to please trust him and help to stop Annoying Orange by voting for the most likely opposition. that's what happens when winner takes all, people end up having to settle for less just to avoid their worst