At the beginning, Little Napoleon.
Later, some of them were calling him a Copperhead (anti-war Democrat)
General George McClellen.
Lincoln fired several generals. He fired McClellan twice.
He was a major general in the civil war, appointed to the position of general in chief of the US Army 3 times.(http://en.wikipedia.org/wiki/George_B._McClellan)
General George Meade.
George McClellan
Major General George B. McClellan was commanding the Federal Army of the Potomac at the Battle of Antietam.
George G. Meade.
George Gordon Meade was a Northern General, who was appointed as commander of the Army of the Potomac just a few days before the Battle of Gettysburg, in which he was the victor.
Ulysses S. Grant
In June of 1861, General George B. McClellan rose to national prominence by his actions in western Virginia. He commanded a small force of Union soldiers that ousted Confederates there and the South could never regain that pro-Unionist section of Virginia which eventually became the state of West Virginia. This was great news in the North and McClellan's name became known in Northern newspapers.
McClellan was a Union commander and he repelled general Lee's first Northern invasion.
George McClellan