MOTIONING TO PROCEED…. Going into today, Senate Democrats had lined up 58 votes in support of bringing health care reform to the floor for debate. Every Republican in the chamber hoped to kill the initiative before the discussion could even begin, and two center-right Southern Dems remained on the fence.

This afternoon, one of the two made the right call

Senate Majority Leader Harry Reid’s hopes of pushing ahead with a sweeping health reform plan got a boost Saturday when Sen. Mary Landrieu (D-La.) said she will vote to start debate.

“My vote today to move forward on this important debate should in no way to be construed as … an indication of how I might vote as this debate comes to an end,” she warned in comments on the Senate floor. “It is a vote to move forward…. But much more work needs to be done.”

…and about two hours later, the other followed suit.

Senate Democrat Blanche Lincoln of Arkansas said Saturday she will support bringing the Senate health care reform bill to the floor for debate, giving Democrats the 60 votes they need to prevent a Republican filibuster.

“Although I don’t agree with everything in this bill, I believe it is important to begin this debate,” she said. “This issue is very complex. There is no easy fix,” she said in making her announcement on the Senate floor, just hours before Saturday night’s 8 p.m. procedural vote.

Barring any extraordinary surprises, there are now 60 votes to bring health care reform to the floor for a debate, at which point plenty of amendments will be considered. It’s the first key procedural hurdle — the vote is still scheduled for 8 p.m. — and senators will begin the next phase of the process a week from Monday.

Pay particular attention to the talk about public option “triggers,” which lingers despite opposition from the left and right. Brian Beutler reports this afternoon that Landrieu told reporters “she thinks Senate Majority Leader Harry Reid will soon have to choose between a triggered public option and no health care bill. She also says Sen. Chuck Schumer (D-NY) — the third-ranking Democrat in the Senate one of its most fierce and vocal public option advocates — has been tasked as a point man on the issue.”

A variety of conversations have been underway this week, most of them surrounding Sen. Tom Carper (D) of Delaware, who’s been working on various public-option compromises for months. Carper has been talking to Landrieu, Schumer, and even Sen. Olympia Snowe (R-Maine) about some kind of deal. Given the nature of the discussions, it’s safe to assume the deal will include a public option provision that’s even weaker than the one currently in the Senate plan.

With that in mind, we’ll likely run into the same dilemma that’s been apparent for quite a while — keep the public option and the reform bill will likely die because center-right Dems won’t accept it; compromise even more on the public option and the reform bill will likely die because center-left Dems won’t accept it.

Expect plenty of arm-twisting, deal-making, needle-threading, and legal bribery in the near future*.

* updated

Our ideas can save democracy... But we need your help! Donate Now!

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.