When the dust settled after Tuesday night's filibuster, the Senate appeared to be basically where it was the day before; Majority Leader Harry Reid [3] (D-Nev.) tabled the controversial measure to set timelines for the withdrawal of most American troops from Iraq and the legislators went home to get some sleep before preparing to take up other business. Looking back just a year, however, it becomes clear an inexorable momentum has started to build in that chamber towards using its power of the purse (i.e. cutting off funding) to end the Iraq War as we know it.

Wednesday morning's 52-47 vote in favor of ending a filibuster [4] by Senate Republicans fell short of the 60 votes required to get an up-or-down vote on the measure. Without a simple majority to defeat the bill outright, the filibuster had been the only tool left to the Republican leadership once Reid initiated debate. Had the measure passed, it would have amended the 2008 defense budget to require President Bush to begin a reduction in U.S. troop levels [5] in Iraq within 120 days down to the "minimum force levels required to protect United States national security interests" by Apr. 30, 2008.

The Reed-Levin amendment -- named after sponsors Sens. Carl Levin [6] (D-Mich.) and Jack Reed [7] (D-R.I.) -- was actually a more aggressive version of a bill brought by the two senators in June 2006. That bill had merely suggested a phased withdrawal of troops to begin later in 2006, but had set no timetable or suggested a date for its completion. Despite the weaker language, that bill was defeated 39-60, with six Democrats opposing it and just one Republican, Sen. Lincoln Chafee [8] (R-R.I.), supporting it.

Contrast that with Wednesdays' vote to end the Republican leadership's filibuster, which had the support of every Democratic-caucusing senator except Connecticut Independent Joe Lieberman [9] (Reid's "nay" vote was merely a procedural tactic) plus four Republicans: Susan Collins [10] (R-Maine), Chuck Hagel [11] (R-Neb.), Gordon Smith [12] (R-Ore.) and Olympia Snowe [13] (R-Maine) (though Collins indicated that while she supported allowing a vote on it, she would have ultimately voted against it).

Following his failure to break the filibuster, Reid pulled the entire Defense spending bill, which would fund all of the Pentagon's activities in 2008, from the Senate floor. He promised to return to it when Republicans pledge to refrain from filibustering the other Iraq-related amendments many probably find equally objectionable. They include:

• An amendment by Sen. Russ Feingold [14] (D-Wisc.) to cut funds for the war: Would require that U.S. troops begin leaving Iraq within 120 days and cut off funds for the war on Apr. 1, 2008. (more details [15])
• An amendment by Sen. Hillary Clinton [16] (D-N.Y.) to revoke the original war authorization: Would revoke the authorization to go to war in Iraq originally passed by Congress in 2002. (more details [17])
• An amendment by Sens. Richard Lugar [18] (R-Ind.) and John Warner [19] (R-Va.) calling for an exit strategy: Would require that by Oct. 2007, President Bush submit to Congress a plan to redeploy U.S. troops from Iraq, and also call for a new National Intelligence Estimate (NIE) on the prospects of Iraq's political stability. (more details [20])

Because the House has passed a bill very similar to the Reed-Levin amendment (the Responsible Redeployment from Iraq Act [21], passed by 223-201 last week), any withdrawal measure passed by the Senate will likely receive a friendly reception there, setting the stage for another confrontation with Bush.

The course, then, depends largely on the several Republicans who have expressed support for withdrawal timelines but voted against ending the filibuster, including Sens. Norm Coleman [22] (R-Minn.), Pete Domenici [23] (R-N.M.), Richard Lugar [18] (R-Ind.), George Voinovich [24] (R-Ohio), and John Warner [19] (R-Va.). Regardless of whether you support or oppose withdrawal timelines, it is clearly important to know exactly where these senators and others like them stand. Want some clarity? Help your fellow citizens out by participating in this week's Congresspedia collaborative project [25] to document their public statements in order to gauge which way the political wind is blowing.