From Wikipedia:
After the war, McClellan and his family departed for a lengthy trip to Europe (from 1865 to 1868), during which he did not participate in politics. When he returned, the Democratic Party expressed some interest in nominating him for president again, but when it became clear that Ulysses S. Grant would be the Republican candidate, this interest died. McClellan worked on engineering projects in
New York City and was offered the position as president of the newly formed
University of California.
[67]
McClellan was appointed chief engineer of the New York City Department of Docks in 1870, a position that did not demand his full-time attention because, starting in 1872, he also served as the president of the
Atlantic and Great Western Railroad. He and his family returned to Europe from 1873 to 1875.
[68] In 1877, McClellan was nominated by the Democrats for
Governor of New Jersey, an action that took him by surprise because he had not expressed an interest in the position. He was elected and served a single term from 1878 to 1881, a tenure marked by careful, conservative executive management and minimal political rancor. The concluding chapter of his political career was his strong support in 1884 for the election of
Grover Cleveland. He hoped to be named secretary of war in Cleveland's cabinet, a position for which he was well suited, but political rivals of his from New Jersey were able to block his nomination.
[69]
McClellan's final years were devoted to traveling and writing. He justified his military career in
McClellan’s Own Story, published posthumously in 1887. He died unexpectedly at age 58 at
Orange, New Jersey, having suffered from chest pains for a few weeks. His final words, at 3 a.m.,
October 29,
1885, were, "I feel easy now. Thank you." He is buried at
Riverview Cemetery in
Trenton.
[70]
He wrote his own version in a book titled
McClellans Own Story. Much of his thinking and frame of mine can be gleaned from his many letters to his wife, many of which can be found in
The Civil War Papers of George B. McClellan: Selected Correspondence, 1860-1865 edited by Stephan W. Sears. Sears also wrote a biography of the general,
George B. McClellan: The Young Napoleon.
McClellan fans may like to visit this Mac friendly website:
http://www.georgebmcclellan.org/