Two late October polls showed Trump with between a 19 and 29 point lead in the state.
In the past 60 years, Idaho has voted for a Democrat only once. Mitt Romney beat Barack Obama by 32 points in the state four years ago. For Idaho's 1.6 million residents, drug addiction was a top issue in the election.
Some of the state's Republican elected officials wavered in their support of Trump. Senator Mike Crapo endorsed Trump, withdrew his support in the wake of Trump's leaked comments boasting about sexual assault, and then later re-endorsed him.