By MICHAEL FALCONE ( @michaelpfalcone )

NOTABLES

• TODAY IN THE SENATE: This evening the Senate votes on the Keystone XL pipeline. There will be only one vote on final passage which requires 60 votes. According to ABC's ARLETTE SAENZ, as of yesterday's whip count, supporters only had 59 votes but Sen. Mary Landrieu, D-La., insists she has 60 - maybe even more. Last night, Sen. John Hoeven, the lead Republican co-sponsor of the Keystone pipeline bill, was a bit more cautious, saying there are a few maybes they hope to switch to "yes" tomorrow. Two senators to keep an eye on will be Angus King of Maine and Chris Coons of Delaware, who told ABC he currently thinks it should be the president's decision but he is listening to the arguments of members of his caucus and his home state.

• WHAT WE KNOW - AND DON'T KNOW - ABOUT OBAMA'S IMMINENT IMMIGRATION ACTION. President Obama could unveil as soon as Friday his planned, unilateral overhaul of the nation's immigration system. Details of the proposed measures remain under wraps, but senior administration officials have said Obama is prepared to "go big." Homeland Security Secretary Jeh Johnson said the administration is in the "final stages" of developing the plan, which he described as comprehensive, touching all aspects of American immigration including border security. ABC's DEVIN DWYER takes a look at what we know - and don't know - about Obama's immigration plan. http://abcn.ws/1xQqq8K

THE ROUNDTABLE

ABC's JEFF ZELENY: The number of the day is 60. Will Sen. Mary Landrieu's fight for the Keystone pipeline prevail or fail by one vote? She starts the day with 59 known supporters: All Republicans and a small group of Democrats. While outgoing Senate Majority Leader Harry Reid has pledged to round up enough support for the bill in an urgent effort to try and salvage Landrieu's Louisiana Senate seat, the White House isn't helping with the arm-twisting. If President Obama carries through with his veto threat - before possibly approving it next year - there's little incentive for a Democrat to walk the plank. Will this be the time lessons are learned that the 60th vote is the worst place to be?

ABC's JORDYN PHELPS: Can Sen. Mary Landrieu's "hail Mary" Keystone effort save her? It's a big day for Landrieu as the Senate prepares to vote on whether or not to approve the Keystone Pipeline - a vote that's only moving forward in the lame-duck session as a favor to the embattled Democrat facing a tough run-off election in three weeks' time. The bill's passage would be a demonstration of Landrieu's campaign message: that her clout and ability to work across the aisle deliver real results for Louisiana. But even if the bill passes (and that's a big "if"), it's unclear how the legislative victory will translate into an electoral one for Landrieu, who still faces many hurdles on the road to reelection. Though Landrieu finished slightly ahead of her Republican challenger Rep. Bill Cassidy in the general election, Cassidy has since gained the endorsement of the third-place candidate Col. Rob Maness as well as a number of Republican stars, such as Sen. Rand Paul. And while Republicans have rushed in to support Cassidy, Democrats have shown little appetite to invest in the race and have even pulled some previously reserved funds. Another challenge for Landrieu is how to make up for her paltry performance among white voters. She captured only 18 percent of that constituency in the general election but needs closer to 30 percent if she is to have any hope of winning on Dec. 6.

ABC's RICK KLEIN: It must be lonely being Mary Landrieu these days - unless you count the protestors who not-so-helpfully inflated a pipeline outside her Capitol Hill home Monday. That's just part of what makes for this peculiar scene. Landrieu is in a runoff fight for her Senate seat, a situation she's become sort of used to in Louisiana. But after months where nearly everything done or not done by President Obama and Senate Democratic leaders were driven by politics, suddenly the policy moves are being made independent of politics - or with comfort in sacrificing Landrieu's career. First, she may not get the votes she needs to pass the Keystone Pipeline in the Senate, which would mark a bitter disappointment that undermines her claims to Washington influence. She needs 60 votes for the bill because Democrats are effectively setting that threshold, mounting what fits the definition of what they've labeled a filibuster when Republicans have done the same. If it passed, a presidential veto is near certain, even though it's an open secret that a similar bill passed in January or February - that is, not by Landrieu's current efforts - could be signed by President Obama. And Obama has made clear that for all the timing considerations he's thinking about with regard to immigration, the runoff in Louisiana is not among them. Maybe Landrieu's fate was sealed when she didn't come close to a majority Nov. 4. But do Democrats - and the outside groups that want a Democratic Senate - think they will have a better chance to secure a Senate seat in a red Southern state any time in, say, the next two decades?

WHAT WE'RE WATCHING

THE SPY WHO INFILTRATED CONGRESS: MEET REP.-ELECT WILL HURD. As a CIA undercover officer, Will Hurd made it his business to go unnoticed. But as a newly-elected member of Congress, this spy has thoroughly blown his former cover. On his first trip to Washington since being elected, the Texas Republican - the first black Republican elected from that state since Reconstruction - told ABC's JEFF ZELENY, host of "The Fine Print," how his years working in the CIA inspired him to come out of the shadows and into the political spotlight. "One of the other things I had to do was brief members of Congress, and when I was in the agency I was shocked by the caliber of some of our elected officials and decided to do something about it," Hurd said. "My mamma said, 'You're either part of the problem or part of the solution,' and so I decided to run." What shocked Hurd most, he said, was that many members didn't even know the basic difference between Sunni and Shi'a Muslims while the U.S. was engaged in wars in Iraq and Afghanistan. WATCH: http://yhoo.it/1uDkM9e

THE BUZZ

with ABC's KIRSTEN APPLETON

FBI WARNS FERGUSON DECISION 'WILL LIKELY' LEAD TO VIOLENCE BY EXTREMIST PROTESTORS. As the nation waits to hear whether a Missouri police officer will face charges for killing unarmed teenager Michael Brown in Ferguson, Mo., the FBI is warning law enforcement agencies across the country that the decision "will likely" lead some extremist protesters to threaten and even attack police officers or federal agents, ABC's MIKE LEVINE, PIERRE THOMAS, JACK DATE and JACK CLOHERTY report. Peaceful protesters could be caught in the middle, and electrical facilities or water treatment plants could also become targets. In addition, so-called "hacktivists" like the group "Anonymous" could try to launch cyber-attacks against authorities. "The announcement of the grand jury's decision … will likely be exploited by some individuals to justify threats and attacks against law enforcement and critical infrastructure," the FBI says in an intelligence bulletin issued in recent days. "This also poses a threat to those civilians engaged in lawful or otherwise constitutionally protected activities." http://abcn.ws/1vlc1BW

OBAMA ORDERS FULL REVIEW OF HOSTAGE NEGOTIATION POLICY. ABC's JOHN PARKINSON reports President Obama has ordered a comprehensive review of policy dictating how the U.S. government tries to secure the freedom of Americans held hostage by terrorists abroad, a senior Pentagon official revealed in a recent letter to a member of Congress. "As a result of the increased frequency of hostage-taking of Americans overseas, and the recognition of the dynamic threat posed by specific terrorist groups, the President recently directed a comprehensive review of the U.S. Government policy on overseas terrorist-related hostage cases, with specific emphasis on examining family engagement, intelligence collection, and diplomatic engagement policies," Christine Wormuth, the undersecretary of defense for policy, wrote in a Nov. 11 letter to Rep. Duncan Hunter, R-Calif., obtained by ABC News. http://abcn.ws/1xJTldt

OBAMA 'WOULD ORDER' U.S. TROOPS INTO COMBAT IF ISIS GOT NUCLEAR WEAPON. President Obama has been unwavering and definitive in declaring he will not deploy U.S. ground troops into combat to fight ISIS militants. Period. But for the first time since the start of the anti-ISIS offensive dubbed Operation Inherent Resolve, the president volunteered a scenario which he said would change his mind, ABC's DEVIN DWYER reports. "If we discovered that [ISIS] had gotten possession of a nuclear weapon, and we had to run an operation to get it out of their hands, then, yes," the president told reporters at a news conference in Brisbane, Australia, on Sunday. "I would order it." http://abcn.ws/1yeH402

IN CASE YOU MISSED IT

-SEN. TED CRUZ JOINS VINE. "A simple message: #DontMessWithTheNet!" https://vine.co/v/O50UXv7nbae

- SEE THE GIANT INFLATABLE KEYSTONE PIPELINE ON MARY LANDRIEU'S LAWN. Sen. Mary Landrieu got a big surprise Monday morning when protesters placed a 30-foot-long inflatable pipeline on the front lawn of her Washington, D.C., home. ABC's ARLETTE SAENZ reports more than two dozen activists assembled on Landrieu's lawn to protest the Keystone XL pipeline, a project Landrieu, D-Louisiana, has championed and pushed the Senate to vote on this week. http://abcn.ws/1A84SGX

WHO'S TWEETING?

@daveweigel: I love that we have a political kingmaker named "King." Next we need a bumbling senator named "Gaffe." http://www.desmoinesregister.com/story/news/politics/2014/11/18/steve-king-kingmaker-summit-iowa-freedom-presidential-candidates/19208555/ …

@bridgetbhc: New members have arrived for the class photo with a quite a few brave souls not wearing winter coats

@ZekeJMiller: Nancy Pelosi on Tammy Duckworth: No doctor's note situations http://www.politico.com/story/2014/11/nancy-pelosi-tammy-duckworth-doctors-note-112966.html … via @POLITICO

@AriFleischer: A gov shutdown did not help the GOP the last 2 times it was done. I get the desire to "stop" O's exec order, but 3rd time won't be a charm.

@FusionIsNews: One in every 30 children in the U.S is homeless: http://fus.in/1u5FPff