The Democrats have a serious advantage right now, that if past history is any indication, they do not know they have.
The Republicans were masters of bringing up legislation that would force Democrats to take unpopular or at a minimum get them on the rcord for future campiagn ads. A Constitutional amendment to ban Gay marriage is a perfect example.
The Advantage is too use this same tool. The american people clearly want an end to the war in Iraq, either now or a timeline for withdraw. The Republicans clearly do not and will vote to block any action that even slightly resembles a timeline or withdraw. They will be forced day after day to stand up and tell the american people why their opinion is irrelevent. How people who have that opinion (most americans) are "cut-n-runners" or worse not "supporting the troops".
Why the Dems are so scared to take a step that most americans support I'll never understand. Even if the effort fails which I'm sure it would, with republic filibuster power, the american people will remember who was on the wrong side of democracy.