Democrats are mostly against all wars and have been since the venture in Vietnam went sour (here in America, not there in Vietnam). Democrats flocked to Kerry when it seemed that his war record -- coupled with his sort-of, sometimes opposition to the war in Iraq -- would legitimate their knee-jerk antiwar stance.
When you live by a candidate's war record, you die by the candidate's war record. Kerry's candidacy is beginning to die the death of a thousand swift cuts.