IMO, Democrats so despise Trump that come election day they will flock to the polls to defeat him and I don't see the Greens taking enough votes away from Hillary to matter. I think with a viable or even likeable candidate, the Republicans could win this election but they decided to roll out the only figure as polarizing as Sarah Palin.
Gary Johnson will have a solid outcome as he'll draw the votes of people like me who could never put in a vote for either Clinton or Trump.