The poll shows the war is the least popular in recent U.S. history. Gallup has similar numbers.
From CNN:
Just 17% of those questioned say they support the 12-year-long war, down from 52% in December 2008. Opposition to the conflict now stands at 82%, up from 46% five years ago.
CNN Polling Director Keating Holland notes that "Opposition to the Iraq war never got higher than 69% in CNN polling while U.S. troops were in that country" and no more than 6 in 10 disapproved of the Vietnam War while troops were on the ground.
Incidentally, one thing Americans approve of less than the Afghan War (17%) is Congress (14%).