NELSON: A LOST CAUSE?…. When his effort to add Stupak amendment language to the health care reform bill came up far short, Sen. Ben Nelson (D) of Nebraska said the vote “makes it harder to be supportive” of the bill. Asked if he now opposes the legislation, Nelson said, “Not at this point in time.”

That was Tuesday. Nelson is sounding more and more like a lost cause now.

Even if all other issues on the health bill are resolved, abortion remains the hardest for Nelson. Regardless of the wording, he demands one result: no federal abortion funds.

“If I don’t get it, I can’t support cloture [ending the filibuster] on the next round,” he said.

In the larger dynamic, there are a variety of measures in play as part of reform, which are no doubt familiar to those following the debate — the public option, Medicare buy-in, triggers, mandates, subsidy rates, implementation timelines, caps, etc. The goal for most reform advocates is to get as many progressive provisions added to the final bill as possible, to take as big a leap forward as can be achieved.

The thing about the Stupak language is that it’s simply not doable precisely because it’s a step backwards. It’s possible to have a worthwhile reform bill that lacks all kinds of meaningful, valuable measures — the difference is over how many steps forward we can take with this piece of legislation, a few or a lot. Nelson not only wants to undermine a variety of progressive goals, he’s apparently prepared to join a Republican filibuster to kill reform unless he’s able to turn back to the clock on women’s basic legal rights.

In other words, Dems are prepared to compromise on a public option; it can always be added later. But Dems aren’t going to turn back the clock on Americans’ reproductive rights — party leaders want to leave the status quo in place, and Nelson, like Stupak, believe that’s not good enough.

Note, Nelson seems to be moving to the right with each passing day, becoming more hostile to crossing the finish line, not less. He had a favorable attitude towards the Medicare buy-in compromise, then started to change his mind. Nelson was satisfied with the Finance Committee’s compromise language on indirect abortion funding, now he’s not.

Roll Call reported this week that some on the Hill believe Nelson’s support is “appearing unattainable.”

So I guess that makes Olympia Snowe, Susan Collins, and Joe Lieberman the most important people in the known universe?

Steve Benen

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.