Olympia Snowe (R-Maine) was always going to be a tough get for the DREAMers. Though she voted for the bill three years ago she’s up for re-election in 2012, her home state just elected a Republican governor, and she’s worried about a possible Tea Party primary challenge. Add to all that the fact that she’s made something of a career of raising and then dashing Dems’ hopes on close votes, and it wasn’t hard to predict what was likely to happen.

Last night, according to a statement published on the conservative National Review website, Snowe made it official.

“Millions of illegal immigrants could attempt to become legal residents as a result of this proposal, according to some estimates,” she said, and that can’t be allowed to happen. Never mind that eligibility for the DREAM Act has always been restricted, and was narrowed further by recent concessions by its sponsors. Never mind that the legal residency process it would establish is long and arduous. Never mind that Snowe voted for a broader version of the bill in 2007. She’s got an election to win.

If Snowe’s “no” vote is confirmed, it’s a huge blow to an already imperiled bill. A few days ago the White House said they anticipated needing seven Republican votes to make the DREAM Act a reality. At the time I could only come up with six plausible GOP votes for the bill, and Snowe was one of them. Without her, I don’t see how the math can be made to work.

It’s been clear for a long time that winning the Senate was going to be tough, and the odds have grown longer in recent weeks.

Right now they’re very long indeed.

9:30 am Update | The US Senate is scheduled to convene in moments to take up the DREAM Act, with a vote expected before noon. Note that today’s vote will be what’s known as a “cloture” vote, with supporters needing 60 votes out of the 100 in the Senate to bring the bill to the floor for discussion.

11:30 am | The Senate is now voting … but not on cloture. Last night the House passed an amended version of the DREAM Act, and both the House and Senate need to pass identical bills to send them to the President. So Majority Leader Harry Reid asked the Republicans to allow the Senate to vote on the House version today. They refused. So now the DREAM Act’s supporters have moved to table the original bill so that the House version can be brought up in its place.

11:50 am | The motion to table passed in a 59-40 vote, which means that the Senate will be free to consider the House version of the DREAM Act next week. Democrats overwhelmingly voted for the motion, Republicans overwhelmingly against, with most of the exceptions being DREAM Act fence-sitters. What tea-leaf-reading this makes possible is something I don’t know, but will try to find out. (Update: See 12:55 below — this vote tells us nothing.)

12:40 pm | CNN is reporting, incorrectly, that today’s vote killed the DREAM Act. MSNBC gets it right.

12:50 pm | Immigration policy blog MicEvHill.com says Harry Reid “pulled a procedural rabbit out of his hat” today, and may have given the bill’s chances of passage a boost.

12:55 pm | I’ve looked at the roll call on today’s vote, and I’m not seeing any patterns that are of any use. On-the-fence Republican Lisa Murkowski voted for the measure, but so did four GOP senators who are known DREAM Act opponents. On the other side of the aisle, DREAM Act skeptic Mark Pryor voted against, but so did three Democratic supporters of the bill.