Nothing’s certain but one of them looks solid and, given Pelosi’s margin, even one is potentially disastrous. Let’s start with the solid. Blue Dog Michael Arcuri, come on down!

Arcuri, who voted in early November in favor of the House version of the health care bill, said he is against the Senate bill for three main reasons:

* He doesn’t want to see the bill passed as a “mega bill,” and he believes more success would be had by breaking the bill apart and passing aspects of it incrementally, he said.

* Arcuri also said he isn’t comfortable with the possible Democratic strategy of passing the bill through reconciliation. This would get around Republican opposition by having the House pass the Senate bill, then the Senate would make amendments requested by the House, and the House would pass the new Senate bill. In other words, a Republican filibuster in the Senate could likely be avoided.

* The Senate bill differs from the House bill in ways Arcuri said he dislikes. He cited a provision that would tax benefits on insurance policies, expand Medicaid eligibility, provide an unfairly low amount of funding to the state and not allow for negotiations on prescription drug prices.

No surprise. He’s a red-district Democrat who likes his job. If it’s surprises you want, try this one on for size:

An influential House progressive says he’s less likely to vote for the final healthcare reform bill now that the White House has incorporated Republican ideas — which could indicate a serious problem is brewing among liberals as Democratic leaders try to figure out a way to finish work on the legislation.

“As I weigh it, I think — for me — a ‘no’ vote is something that I continue to lean toward,” Rep. Raúl Grijalva, D-Ariz., the co-chairman of the Congressional Progressive Caucus, told Salon in a brief interview off the House floor Wednesday. “Especially the last additions — that was kind of a slap in the face for all of us who fought for the public option.”…

[Obama’s health savings account] provision “was, when we were in the minority, something that we fought tooth and nail to keep out [of legislation],” Grijalva said. “I find that ironic — something that we had fought to keep out, and indeed were successful, gets back in as part of reconciliation. And a public option that enjoys great support in the House and up to 30 senators gets left out. That’s something I just don’t understand.”

Not only won’t the progressive caucus whip its members to vote yes, but Grijalva says he’s “pretty certain” that Kucinich and Eric Massa won’t be the only hard-left liberals to vote no this time because the bill’s not as socialist as they would like. Massa, in fact, could flip to yes to help Pelosi out given the announcement this afternoon that he’s retiring for health reasons (and maybe other reasons too). But don’t bet on it: He’s a committed proponent of single-payer, and as the left is discovering to its dismay, retiring Democrats who voted no in November aren’t automatic yeses this go round. Right, Brian Baird?

In a brief interview with Salon Tuesday night, Baird didn’t sound particularly enthusiastic about the prospect of switching his vote. “I get all these people advocating, calls and letters, saying vote one way or the other,” he said. “I don’t know how they know what’s going to be in it — because I sure don’t.”…

“We’re going to be asked, ‘Okay, up or down,’ on a Senate bill, under reconciliation rules which we don’t know will the Senate vote for it, will it be included under reconciliation,” he said. “So they’re going to say, ‘Okay, vote for this bill, because it would do X,’ but under reconciliation, X may not make it past the parliamentarian’s gate… We’re not sure what’s in it [and] we don’t know whether it’ll pass the Senate anyway.”

Pelosi needs Massa and Baird to cancel out Arcuri and Grijalva, but even if she gets them, she’s only back to the status quo. And the status quo, thanks to the pro-life objections of Stupak et al., means she’s probably 10-12 votes in the hole at the moment. In fact, according to an NYT piece from a few days ago flagged by Geraghty, yet another retiree whom Pelosi was targeting for a flip — John Tanner — has told friends he’s sticking with his no vote. If they can’t get Dems who are already “dead” to change their mind, how are they going to convince Blue Dogs running for reelection to commit kamikaze?

The beauty of Arcuri and Grijalva speaking up, of course, is that it’ll encourage other fencesitters to commit to voting no. The less likely it seems that this thing will pass, the less undecideds have to worry about their vote being the difference and the easier it becomes to abandon ship. Here’s to an imminent dam burst. Via Greg Hengler, I leave you with McConnell’s response to Obama’s speech this afternoon. Given the ideological differences between Arcuri and Grijalva, his point about bipartisan opposition is even truer than it at first seems.