It took nine and a half hours of chipping away at a seemingly infinite stream of amendments — some positive, some poison-pills — but the Senate Environment and Public Works committee favorably reported Joe Lieberman and John Warner’s greenhouse gas bill, America’s Climate Security Act, today.

The process wasn’t easy. Republicans came armed with about 150 amendments, some of which were so toxic and clearly non-passable that it appeared they were simply trying to obstruct or derail the proceedings altogether. Indeed, Senate Majority Leader Harry Reid, aware that the amendment avalanche would take hours to overcome, called the Senate floor to order at noon, two and a half hours later than usual, to help the bill along. It was a procedural move, designed to buy the committee time lest Republicans take advantage of a rule that would have allowed them to derail the entire proceeding. Perhaps thanks to Reid’s maneuvering, that never came to pass.

Unfortunately, neither did a handful of extremely important amendments — introduced by Senators Clinton and Sanders — that would have strengthened ACSA enough to please dark greens, a constituency that has thus far been unimpressed with the bill’s wide array of compromise measures.

At the end of a very long day, though, there were only a couple of surprises. That the bill passed was expected; that the bill was only modestly improved was expected; that Hillary Clinton didn’t show up was expected.

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What wasn’t expected — at least at the outset — was that the whole process would go so smoothly. Yes, it took an extremely long time, but in the end, the minority withdrew or didn’t introduce most of their amendments, and they never overtly attempted to derail the proceedings, allowing the process to be completed within one day.

Then there was the other big surprise: Sen. Bernie Sanders voted to report the legislation favorably out of the committee.

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That represented a major reversal for the Independent from Vermont. At the end of the subcommittee markup process, after watching almost every one of his amendments die at the hands of the bill’s authors, Sanders registered a “no” vote to protest the bill’s weakness compared to … well, compared to his own.

This time around, Sanders met with more success, but only because he offered several uncontroversial amendments. Just as last time, every one of his significant offerings — to improve the forward-looking emissions reduction goal to 80 percent by 2050; to allow the EPA administrator to strengthen the bill in the event that ACSA proved inadequate to the scope of the crisis; improving the auction; requiring CCS technology to be extremely effective — met its maker.

At one point, Sanders seemed to indicate that he still couldn’t support the bill, beseeching his own colleagues, but especially those on the other side of the aisle: “while it is fine that we reach a political agreement here, the scientific community is telling us that the agreement we are reaching here does not do the job that has to be done.” But when the session came to a close at about 6:30 p.m., Sanders voted yes by proxy.

The bill is by no means a fait accompli at this point. Not even close. If it was brought to the floor of the Senate tomorrow, it would face many, many more hours of heated debate, a potentially deadly filibuster, and the real possibility of a presidential veto. This may, in other words, be a symbolic vote.

At this point it’s clearer than ever who supports the bill: Incrementalist environmental organizations on the one hand, and industries convinced that this is the friendliest bill they’ll ever get on the other. Denialists may not be impacting the debate any longer, but neither, apparently, are deep greens, who today may have lost, in Bernie Sanders, the only voice in the Senate that’s been speaking on their behalf.