This is all political grandstanding and maneuvering. The Dems passed this bill knowing Bush would veto it. The last thing they (the Dems) want is serious trouble in Iraq due to funding failures. At the same time, they can claim they tried their best to stop the war and only Bush continued it.

The Dems want the war to go on (unsuccessfully) to the end of Bush's presidency so they can then pull the plug on it with no political penalties. They're not about to force an end to it and give the Reps a chance to get off the hook by blaming them for whatever bad happens after.

The Dems aren't the only cynics in this game, the Reps are just as good at political theater. They're doing everything they can to see to it that if the war does end during the Bush administration Bush can say "we were doing fine until the majority started obstructing us". In the ideal universe for the Reps, the next Dem administration will inherit the unfinished war the same way Nixon inherited Nam from Johnson.

What both sides seem to have forgotten is that while they're playing this cynical game, the situation on the ground could change suddenly and we may be forced to respond to a real emergency.

What if Iran tries a major escalation? What if our Arab allies start denying us bases and staging rights? What if trouble breaks out in some other part of the world? What if we suffer a major battlefield reverse? What if our elected government there starts herding Sunnis into concentration camps? The election is almost two years away, anything could happen.