Lincoln's doubts

Meanwhile the Democratic Party split. Peace Democrats, who wanted a negotiated peace at any cost chose as their nominee George B. McClellan, Lincoln's former commander of the Army of the Potomac. Before the election ended even Lincoln expected that McClellan would win.

Abraham Lincoln and George McClellan at Antietam, shortly after the battle of Antietam.

http://www.civilwar.org/books/interviews/long-road-to-antietam.html