By MICHAEL FALCONE ( @michaelpfalcone )

NOTABLES

• WALKING THE WALK: Yesterday Wisconsin Gov. Scott Walker announced the formation of a new political committee that will help him build his presidential campaign, ABC's RICK KLEIN reports. An aide told ABC News this is likely to be the most formal step he takes toward a (very, very likely) presidential announcement until his state budget is concluded around June. The launch of Walker's 527 group, "Our American Revival," was first reported by the Washington Post. Walker was a hit with a folksy, personal, and fiery speech last weekend at the Iowa Freedom Summit, and also appeared at a gathering sponsored by the Koch brothers operation over the weekend in Palm Springs. "Our American Revival encompasses the shared values that make our country great: Limiting the powers of the federal government to those defined in the Constitution while creating a leaner, more efficient, more effective and more accountable government to the American people," Walker said in a statement yesterday.

• READY FOR HILLARY THANKS SARAH PALIN: Remember last weekend when former Alaska Gov. Sarah Palin stood up in Iowa before a group of Republicans and waved the "Ready for Hillary" flag? Well, turns out she inadvertently did the group a huge favor, ABC's LIZ KREUTZ notes. On Monday the pro-Clinton super PAC, Ready for Hillary, sent out an e-mail message to their supporters about the moment. And in response, they've since raised roughly $25,000 in donations, according to the group. "Here's the kicker - by raising $25,000, Sarah officially qualifies as a Co-Chair of our National Finance Council," the message from the group's Executive Director Adam Parkhomenko says. "(We will wait until Sarah calls before officially adding her name to the list.)"

• WHAT ELSE THE KOCH BROTHERS COULD BUY WITH $889 MILLION: Yesterday, we noted the Koch brothers' announcement that they will spend $889 million supporting conservative campaigns in 2016. The financial commitment has been described as "whopping," "staggering" and "historic." It may be all those things, but adjectives aside, the money their vast fundraising network is ponying up this cycle puts them on par with the spending of both the Democratic and Republican parties, each of whom spent a bit more than $1 billion during the 2012 campaign. The Koch's 2016 spending is astronomical, any way you slice it. ABC's ALI WEINBERG compares it to other ways the two political heavyweights could spend this windfall if they woke up tomorrow and decided they no longer wanted to be in politics: http://abcn.ws/1H7xGUk

• ON THE TRAIL: Mitt Romney is in the spotlight with an address this evening at Mississippi State University this evening. Mike Huckabee continues his book tour today making stops in North Carolina. Former New York Gov. George Pataki is back in New Hampshire today, speaking to students at St. Anselm college this evening. -Shushannah Walshe

THE ROUNDTABLE

ABC's RICK KLEIN: Indiana Gov. Mike Pence drew headlines this week for his odd if not just plain ill-conceived state "news" service, sparking enough Pravda and Kim Jong Un Tweets to power a Seth Rogen movie. But the most consequential thing Pence may have done this week, at least when it comes to 2016, is the deal he cut to expand Medicaid using funds available under Obamacare. If Pence winds up running, his move will become a major point of contention; if he doesn't, he's given some other key candidates a strong talking point, maybe even precious cover. This is shaping up as one of the biggest fault lines inside the Republican presidential race. Possible candidates will run the range of outright rejection of Obamacare funds (Jindal, Perry), through special state-specific deals for some expansion (Walker, and now Pence), right up to accepting the money and the coverage expansion that was designed as a key piece of President Obama's healthcare overhaul (Christie, Kasich). And, of course, we'll have the senators in the field, who can - and almost surely will - take the clean stance that any acceptance of Obamacare funds is abetting a fatally flawed program.

ABC's SHUSHANNAH WALSHE: Scott Walker's launch of his "Our American Revival" political committee Tuesday could not have happened at a better time, fresh off his well-received speech last weekend at the Iowa Freedom Summit. Whether the roll-out was long planned or not, using the momentum from his star turn is a perfect way to keep the 2016 story on him over his potential opponents. It's a 527 not a leadership PAC, like possible rivals Jeb Bush and Chris Christie have recently set up, but he will still be able to use the funds to travel to early states or donor meetings. And speaking of donors, like a PAC, it gives a spot for early supporters to place funds ahead of a full-fledged campaign.

ON THE ROAD WITH POTUS

-FIRST LADY'S VISIT TO SAUDI ARABIA SENDS STRONG MESSAGE ABOUT WOMEN. In a country where women have few rights, First Lady Michelle Obama yesterday seemed to lead by example. There she was, standing side-by-side with her husband as he stepped off Air Force One in Riyadh Tuesday, where, during a brief visit, the president offered condolences for the recent death of King Abdullah and met with his successor, King Salman. According to ABC's MARY BRUCE, the first lady accompanied the president throughout the stay, embodying some of the reforms that her husband is pushing the country to adopt. Wearing pants and her head uncovered, Mrs. Obama stood dutifully beside her husband as he shook hands with the Saudi delegation on the airport tarmac Tuesday morning and again at Erga Palace on the outskirts of Riyadh. Due to the cultural constraints, the first lady purposely stood slightly behind her husband and waited for a gesture to be made to her by the men in the receiving line. If one of the men initiated a handshake she returned, if not then she simply smiled or nodded politely. http://abcn.ws/1JC1iqO

-7 HINDI LINES OBAMA DROPPED IN INDIA. http://abcn.ws/18qoA5R

HAPPENING ON THE HILL

with ABC's VERONICA STRACQUALURSI

BENGHAZI COMMITTEE CHAIR TREY GOWDY: HILLARY CLINTON 'NEEDS TO BE TALKED TO.' Rep. Trey Gowdy, chairman of the House Select Committee on Benghazi, said Tuesday he still intended to summon former Secretary of State Hillary Clinton to testify as part of the investigation into the 2012 attack on the U.S. diplomatic compound in Libya that killed four Americans, ABC's JEFF ZELENY writes. "Every witness who has relevant information needs to be talked to," Gowdy told reporters after a committee meeting Tuesday. If he didn't call Clinton before the committee, Gowdy said, it would be "an incomplete investigation." The House Select Committee on Benghazi is charged with delivering the final word on the attack, which has been the subject of an intense political battle. http://abcn.ws/1z053TN

HOUSE SPEAKER JOHN BOEHNER THREATENS SECOND LAWSUIT AGAINST OBAMA ON IMMIGRATION. Speaker John Boehner told House Republicans in a closed-door meeting Tuesday that a lawsuit might be the best - or only - option to try and overturn President Obama's executive action on immigration, ABC News has learned. "We are finalizing a plan to authorize litigation on this issue, one we believe gives us the best chance of success," Boehner told GOP lawmakers at their weekly conference meeting, according to a Republican official in the room. One month before the Homeland Security Department runs out of funding, Republican leaders are scrambling to find alternative ways to express their displeasure over the president's decision last year to grant work visas to up to five million undocumented immigrants, ABC's JEFF ZELENY and JOHN PARKINSON report. http://abcn.ws/1tloiGu

WHO'S TWEETING?

@kenvogel: SCOOP: Rubio wins straw poll of Koch donors. Rand Paul, despite being closest to bros' libertarianism, finishes last. http://www.politico.com/story/2015/01/koch-donors-marco-rubio-2016-114673.html?hp=t1_r …

@fschouten: Koch group moves to put brakes on gas-tax hike http://usat.ly/1Cg3nYD via @USATODAY

@brianefallon: Roll Call: Loretta Lynch to Say She Wants Better Relations With Congress http://blogs.rollcall.com/wgdb/loretta-lynch-testimony/ …

@etchaStech: Huck polling above Walker, Cruz, Perry, Rubio RT @politico: Mike Huckabee complains of 'trashy' women at Fox News http://politi.co/1EpMSKq

?@GlennThrush: Scoop: RNC digital guru Chuck DeFeo jumps to Koch Bros via @dsamuelsohn http://www.politico.com/story/2015/01/rnc-digital-operation-114674.html …