By MICHAEL FALCONE ( @michaelpfalcone )

NOTABLES

• HAPPENING TODAY: Omar Gonzalez, the man accused of scaling a security fence and getting into the White House with a knife is scheduled for an appearance today in Federal Court. Gonzalez, 42, of Copperas Cove, Texas, is facing charges of unlawfully entering a restricted building or grounds while carrying a deadly or dangerous weapon. The Army says Gonzalez served from 1997 until his discharge in 2003, and again from 2005 to December 2012, when he retired due to disability.

• NEW SECURITY MEASURES: In the wake of the incident Friday night, the Secret Service stepped up its security procedures at the White House complex, ABC's ARLETTE SAENZ reports. Secret Service Director Julia Pierson ordered an immediate increase in "officer patrols and surveillance capabilities along the Pennsylvania Avenue fence line" of the White House complex, the Secret Service said Saturday. In addition, today The New York Times reports that "The Secret Service is considering screening tourists and other visitors at checkpoints before they enter the public areas in front of the White House … As part of the screening, the Secret Service would establish several checkpoints a few blocks from the White House, the officials said. The screening would likely be limited to bag checks and not include measures taken at airports by the Transportation Security Administration, which include metal detectors and body scans." http://nyti.ms/1mymjeO

• WORD FROM THE WHITE HOUSE: Following Friday's incident, the White House said President Obama has "full confidence" in the Secret Service. "The President has full confidence in the Secret Service and is grateful to the men and women who day in and day out protect himself, his family and the White House," the White House said over the weekend. "The Secret Service is in the process of conducting a thorough review of the event on Friday evening and we are certain it will be done with the same professionalism and commitment to duty that we and the American people expect from the United States Secret Service."

THE ROUNDTABLE:

ABC's RICK KLEIN: We know where Sen. Ted Cruz won't be spending his week. News that former Sen. Bob Dole and Sen. John McCain are set to join forces this week on behalf of Sen. Pat Roberts, R-Kan., confirms Republican panic about the possibility of losing a safe Senate seat just as the majority seems to be in the party's grasp. Kansas has become the most compelling storyline of the election season, with the real possibility that independent candidate Greg Orman scrambles the GOP's national math. If Roberts prevails, there will be something fitting about the party's old guard helping save his seat and, possibly, deliver the majority for the Republican Party. That was a dominant theme of the primary season where the establishment ran up a near-perfect score. But fast-forwarding a few months, what happens if Orman wins? Maybe he's already secretly decided to caucus with the Democrats. But if he's at all on the fence, the attacks emanating from Roberts and now Dole and McCain may make it hard to convince the former College Republicans chapter president to take his weekly lunch with those guys.

ABC's SHUSHANNAH WALSHE: Just weeks away from the midterm elections, one of the most closely watched races in the country is out with another negative ad. Kentucky voters have been bombarded with them, but this time it'S Democratic challenger Alison Lundergan Grimes out with a new television ad asking, "Where was He?" of her opponent, Senate Minority Leader Mitch McConnell. "First we learn Mitch McConnell skipped hundreds of committee meetings. Where was he?," the narrator asks. "He didn't show up to vote on troop funding, the farm bill, and the VA. On days he found time for a lobbyist fundraiser and was on two TV shows." The ad ends accusing McConnell of spending "the rest of the time" creating "gridlock. Thirty years is long enough." The Grimes' campaign wouldn't say how large the buy is, but say it is six figures. Of course Grimes is not the only one running negative ads, McConnell's, as well as his super pac's, have also been negative, some even nasty. But, now so close to the election will these ads possibly sway voters still making up their mind? Is it that one last ad that could sway one more voter? Or have voters already decided and could the bombardment of negative ads actually keep them away from the polls? We won't have to wait long to find out. WATCH: http://bit.ly/1v8iegF

HAPPENING TODAY

REP. JOHN LEWIS HOSTS FACEBOOK Q&A. Today at 5:15 p.m. Eastern, John Lewis - civil rights icon, U.S. Congressman and graphic novelist - will host a live Facebook Q&A at Facebook.com/JohnLewis. Lewis recently released "March: Book One" a graphic novel about his experience in the civil rights movement with co-author Andrew Aydin.

BUZZ

SYRIAN OPPOSITION LEADER: 'WE NEED YOUR ASSISTANCE'. The leader of what is referred to as the moderate Syrian opposition has a message for the world: give us the proper support and we can end the two-pronged war in Syria against dictator Bashar al-Assad as well as ISIS in "three years max," according to ABC's MIKAYLA BOUCHARD. Syrian Opposition Coalition president Hadi al-Bahra will address the United Nations General Assembly in New York on Wednesday to plead for American and western aid to defeat Assad and ISIS militants in Syria. "Currently I am sitting with you and fighting on two fronts. We are fighting in Damascus against the regime, we are fighting in Aleppo against ISIL," Bahra told ABC's BOB WOODRUFF. "We are in the fight and will continue to fight. But we need your assistance. This danger now is not a Syrian issue. It is proved now that it is not a regional issue. It is also expanding now to be threat in Europe and even to the U.S." http://abcn.ws/1pnLqM0

SAMANTHA POWER PREDICTS: U.S. WON'T CONDUCT AIRSTRIKES IN SYRIA ALONE. U.S. Ambassador to the United Nations Samantha Power made the bold prediction Sunday on "This Week" that if the United States should go forward with airstrikes against ISIS targets in Syria, it would not do so alone - even though no country has yet to publicly commit to joining the U.S. in such an effort, reports ABC's BEN BELL. "I will make you a prediction George, which is that we will not do the air strikes alone, if the president decides to do the air strikes," Power told ABC News "This Week" anchor GEORGE STEPHANOPOULOS. "It will be up to each country to announce for itself whether it's prepared to participate, whether in a combat role or to provide military equipment," the U.N. ambassador said earlier in the interview. President Obama will appear in front of the United Nations General Assembly this week as he attempts to strengthen his case for international action against ISIS. Power told Stephanopoulos she believes the U.S. has the legal basis it needs to go forward with action against ISIS without a U.N resolution - one that Russia could potentially veto. http://abcn.ws/1obuSYe

IN CASE YOU MISSED IT

BOB DOLE RETURNS TO SAVE KANSAS FOR JITTERY GOP. It has been a rough two-and-a-half weeks for Kansas Sen. Pat Roberts, a three-term Republican facing his toughest fight for re-election since arriving in Washington in 1981. Roberts, who survived a Republican primary challenge, now finds himself unexpectedly locked in an even more competitive general election fight. But even as he pushes back against criticism that he has been in Washington too long, Roberts is doubling down on his longevity. He's set to get a helping hand from a golden name in Kansas politics: Bob Dole. "The battleground for control of the Senate is now Kansas," Dole, 91, told ABC's ALEXANDER MALLIN. "I think Roberts is going to win." Dole, once a staple of the state and national political scene who served as Senate majority leader and lost to Bill Clinton in a 1996 presidential run, will be campaigning for both Roberts and Gov. Sam Brownback going into the midterm elections. http://abcn.ws/1qiBxiH

WHO'S TWEETING?

@zbyronwolf: Spending on K-12 will decline from $43 billion in '13 to $38 billion in '24… http://money.cnn.com/2014/09/19/news/economy/federal-spending-on-children/index.html … @jjsahadi #Sequestered

@RebeccaRKaplan: The one and (possibly) only time you'll see me tweet about football. Congress has the NFL in its crosshairs: http://www.cbsnews.com/news/congress-has-the-nfl-in-its-crosshairs/ …

@thehill: Peter King blasts handling of White House gate jumper: "He could have had a body bomb. He could have had a vest on." http://ow.ly/BLvn8

@pkcapitol: I still can't believe @SecretService wants to seize more ground outside White House. Just build a higher fence. http://wapo.st/XIKPxP

@ajdukakis: New film by Rory Kennedy uses never-before-seen ftg to tell little-know Vietnam story http://yhoo.it/1mB4sUt @abc @YahooNews #PowerPlayers