 General McClellan failed to maintain the trust of President Abraham Lincoln . He was insubordinate to his commander @-@ in @-@ chief and privately derisive of him . He was removed from command in November after failing to decisively pursue Lee 's Army following the tactically inconclusive but strategic Union victory at the Battle of Antietam , and never received another field command . McClellan went on to become the unsuccessful Democratic Party nominee in the 1864 presidential election against Lincoln . The effectiveness of his campaign was damaged when he repudiated his party 's platform , which promised to end the war and negotiate with the Confederacy . He served as the 24th Governor of New Jersey from 1878 to 1881 . He eventually became a writer , and vigorously defended his Civil War conduct . 
