Durbin fits in with the long tradition of Copperhead Democrats:
Copperheads (politics) in the news
Warning: there is some racist (the " N-word") language in this article. It is simply the language that was used during the American Civil War.
The Copperheads were a group of Northern Democrats who opposed the American Civil War, wanting an immediate peace settlement with the Confederates. They were also called Peace Democrats.
The most famous Copperhead was Clement L. Vallandigham, who was a serious thorn in President Lincoln's side.
More on the Copperhead agenda
They opposed emancipation of American slaves, forming groups to persuade Union soldiers to desert, and helped Confederate prisoners of war escape. The name Copperheads was given to them by Republicans and may have derived from the venomous snake (the Copperhead) that strikes without warning or may have been a reference to the copper liberty-head coins which many wore as badges.
Copperheads opposed turning the Civil war into a total war to destroy the South and restore the Union. They sometimes met with Confederates, aiming at restoring peace.
How they were treated in the Union
As war opponents, they were suspected of disloyalty, Lincoln often having them arrested. In summer 1864, Ulysses S. Grant was bogged down in the Siege of Petersburg and William Tecumseh Sherman getting nowhere in Georgia. At this sad moment for the Union, during midterm election in Lincoln's home state of Kentucky, Lincoln suspended habeas corpus and arresting every Democrat he could round up. The Democrats still swept the July 1864 election in Kentucky.
The Confederates loved the Copperheads and encouraged their activities whenever possible.
Areas of strength
The Copperheads were strongest in Irish Catholic groups (poor Catholics were often anti-war, expecting to lose jobs to newly-freed slaves) in the eastern Pennsylvania coal country, and German Catholic areas of Wisconsin. They were also strong in border areas. They sometimes carried signs reading things such as "The Constitution As It Is, The Union As It Was," or, more offensively, "We won't fight to free the nigger."
Every Union defeat such as the Battle of Chancellorsville led to louder calls from the Copperheads and given the inept Union leadership through much of the war, they had ample ammunition.
The decline of the Copperheads
After the spectacular victory at the Battle of Atlanta in Fall, 1864, and the end in sight of Grant's dug-in siege of Petersburg, the Copperheads declined in influence.