The New-York Times was elated that Maine’s Republican governor Samuel Cony was re-elected. Possibly the “first gun” in the campaign was Vermont’s election of Republicans for all three U.S. House Representatives on September 6th. The same link shows Maine electing Republicans for all five of its House seats on September 11th.
Apparently Copperheads in Maine who found cold comfort in the election results could head west to mingle with more like-minded spirits. From the Richmond Daily Dispatch on September 13, 1864:
A “Copperhead” paradise.
–Idaho and Nevada are said by the Yankee papers to swarm with disaffected and disloyal men. It is estimated that ten thousand men of this class have goes there in the past year and a half. The territories named are a perfect Copperhead paradise. …
Paradise was soon lost in Nevada, which gave its two electoral votes to President Lincoln in the November election. Idaho wouldn’t earn its star until 1890.