By MICHAEL FALCONE ( @michaelpfalcone )

NOTABLES

• U.S. TO ANNOUNCE HACKING CHARGES AGAINST CHINA: The United States government is set to file charges against government officials in China for allegedly hacking U.S. business interests, marking the first time ever that the U.S. government has formally accused another nation of using the Internet to break into U.S. businesses and gain unfair economic advantage, ABC's PIERRE THOMAS and MIKE LEVINE report. The move carries enormous diplomatic implications, as the Justice Department and FBI are expected to announce charges Monday against several Chinese officials, according to sources. The charges will include economic espionage and theft of trade secrets. U.S. intelligence officials have long believed that the Chinese government has been engaged in a state-sponsored campaign to hack U.S. interests and steal research and development. U.S. officials insist such efforts affect national security. http://abcn.ws/1gZq6t9

• DETAILS: The officials getting charged are tied to the Chinese military. In total, five individuals will be named. And charging documents will accuse them of, among other things, stealing information related to a nuclear power plant and information from a company that made solar panels.

• HAPPENING TODAY: A formal announcement is expected this morning in Washington from U.S. Attorney General Eric Holder, the head of the Justice Department's National Security Division, John Carlin, and others, according to THOMAS and LEVINE. The charges will be filed in the Western District of Pennsylvania. It's unclear why the U.S. government chose to file the charges in that district. As soon as the charges are announced, the Chinese officials will become international fugitives. But it's unknown if they will ever be taken into custody. http://abcn.ws/1gZq6t9

THE ROUNDTABLE

ABC's RICK KLEIN: This wasn't supposed to happen anymore. The late-breaking revelation that GOP Senate candidate Monica Wehby - first reported by Politico late last week - was accused of stalking by an ex-boyfriend undercuts a powerful biographical story around the first-time candidate, a renowned pediatric surgeon. And in Oregon, a vote-by-mail state, it may actually have come too late to swing the primary. Instead, the news is likely to help define Dr. Wehby for the general election - undercutting what would always have been a longshot campaign against a Democratic Senate incumbent. More broadly, it undercuts Republican attempts to further expand the Senate field - and serves as a reminder, again, that candidates matter. These aren't the kinds of surprises Republicans were looking for this year.

ABC's MICHAEL FALCONE and LIZ KREUTZ: In case you missed it, Hillary Clinton offered up a personal insight about her family last Friday that speaks volumes about what the 2016 presidential race might be like if she - as many expect - decides to run. "Our motto is 'we're all in this together,'" she said, quoting the Clinton family mantra. "Which we totally believe." And she and her husband, former President Bill Clinton, have been living out those words, hopscotching from event to event, defending each other's record. Hillary and Bill are two halves of the world's most formidable political tag team. Bill has been making sure to talk up his wife's "stamina." Last week the two Clintons attended a total of 14 events. Bill spoke at four events in Washington, attended the Sept. 11 memorial museum opening as well as a political fundraiser. Hillary gave four public speeches, appeared on "The View," and headlined a fundraiser for Chelsea Clinton's mother-in-law who is running for Congress in Pennsylvania. She even spoke at the opening of an art exhibition at the Clinton Center in Arkansas. All in a week's work for the former - and possibly - future president. http://abcn.ws/1lLRdMM

ABC's SHUSHANNAH WALSHE: We are one day away from the biggest primary night we've seen so far. Not all of them are tight, although some are, but more importantly Tuesday truly kicks off the beginning of the 2014 cycle for most of the country. In Kentucky this morning, Sen. McConnell's senior advisor Josh Holmes put out a memo not only saying he is "poised to win a historic primary election" tomorrow, but listing all of the coverage his opponent Matt Bevin has received and how much money Bevin has spent in his battle to topple the senate minority leader. He looked like a serious contender and had support from national groups eager to toss out McConnell, but a series of mistakes throughout his effort, including Bevin addressing a cock fighting rally, revealed a flawed candidate. Not to mention how difficult it is to topple a congressional leader, especially with no political experience. After Tuesday if all goes the way is expected, all eyes will truly turn to Kentucky as we watch the 2014 main attraction kick off. With polls as tight as possible, this will kick off the general election between McConnell and his Democratic opponent, Secretary of State Alison Lundergan Grimes. What we've seen in Kentucky so far will be nothing compared to the bare knuckled brawl we expect to begin in earnest now. And as for Team McConnell they are hoping their likely win Tuesday will bring them, as Holmes put it in his memo today "significant momentum."

BUZZ

KARL ROVE WANTS HILLARY CLINTON TO 'COUGH UP THOSE MEDICAL RECORDS'. GOP strategist Karl Rove doubled down Sunday on his doubts about Hillary Clinton's health, which last week drew a sharp rebuke from former President Bill Clinton, according to ABC's ALI DUKAKIS. "The Center for Disease Control says a concussion is a type of traumatic brain injury," Rove told his roundtable mates on "Fox News Sunday with Chris Wallace," all of whom took issue, at varying degrees, with the former George W. Bush adviser's comments, reported in a headline by the New York Post's "Page Six," that "Hillary may have brain damage" from a 2012 concussion. "I'm not questioning her health. What I'm questioning is whether or not it's a done deal that she's running, and she would not be human if she … did not take this into consideration," Rove said while dodging fire for his comments. "She'll be 69 at the time of the 2016 election. If she gets elected and serves two terms, she'll be 77." After Rove's initial comments last week, former President Bill Clinton defended his wife and lashed out at Rove and conservatives. "First, they said she faked her concussion and now they say she is auditioning for her part on 'The Walking Dead,'" Bill Clinton said at the Peter G. Peterson Foundation's 2014 Fiscal Summit. "I must be in really tough shape because she is still quicker than I am." http://abcn.ws/1lRjdOW

-CHENEY SPEAKS: Chris Wallace was also joined by Dick and Lynn Cheney on Sunday, and the former vice president, who had his own health problems during his tenure in the White House, offered his thoughts on Clinton's concussion. "I think any presidential candidate or vice presidential candidate is going to have to answer questions about their health," Dick Cheney said. "I wouldn't want to pre-judge Mrs. Clinton's health. I don't know about it. "I felt responsible to be open about my health when I was vice president and a candidate," he added. "[It's] expected of anyone running."

-RNC CHAIRMAN REINCE PRIEBUS: Echoing Cheney's sentiment, Republican National Committee Chairman Reince Priebus said Sunday that if Clinton did suffer a brain injury, it would bring into question her capability to perform her duties as commander-in-chief. "I'm not a doctor," Preibus told NBC's "Meet the Press." "What I do know is that the issue is going to come up, as it does for any person running for president."

BILL KRISTOL ADMONISHES KARL ROVE FOR HILLARY CLINTON HEALTH COMMENTS. ABC News contributor and Weekly Standard editor Bill Kristol admonished fellow Republican Karl Rove Sunday on ABC News' "This Week," asserting that his choice to weigh in on the health on former Secretary of State Hillary Clinton was not an especially smart move, notes ABC's BEN BELL. "I don't think it was a particularly shrewd move," Kristol said. "I mean, we'll see how Secretary Clinton's health is. She'll be out there campaigning, presumably. I imagine her health will be fine. But, in any case, people can see for themselves, so there's no reason for Karl Rove to speculate about it." Peggy Noonan, a columnist for the Wall Street Journal, told the "This Week" roundtable that the brouhaha might even help the former first lady as the 2016 presidential election gets closer. "I don't think it was helpful for a political operative, as opposed to journalists, to begin this whole story," Noonan said. "But I also think, in a funny way, this will work for Mrs. Clinton's benefit after all. She's got a book tour coming up in June that means these topics will come up then, when she's selling the book, when she's doing network specials, when she's feeling fresh and perky and can knock it back with prepared lines, so I think its fine. But sure, it's an early move of 2016." http://abcn.ws/1hW1Ng2

PENNSYLVANIA LEGISLATOR TAKES ON THE CLINTON MACHINE IN FIERCE PRIMARY. Meet the man who's trying to beat the Clinton family at its own game. On Tuesday, Marjorie Margolies, an in-law of the Clintons will be in a four-way brawl in a primary in the Keystone State. But the man who may best her doesn't come from political royalty and he isn't even independently wealthy, ABC's BETSY KLEIN notes. He's a 37-year-old baby-faced state legislator who grew up in a rowhouse in Philadelphia. "Marjorie puts Bill Clinton in her ads, I put my dad in my videos," Brendan Boyle said of his father, who is a janitor for the Southeastern Pennsylvania Transportation Authority. Boyle is up against Margolies, a professor at the University of Pennsylvania and former journalist who held the same office she is seeking from 1993 to 1995. She lost her seat after casting a controversial vote in favor of Bill Clinton's budget. She also happens to be Chelsea Clinton's mother-in-law. Her son Marc Mezvinsky married Chelsea Clinton in July 2010 and they are expecting a baby this fall. His other primary opponents are state Sen. Daylin Leach and physician Val Arkoosh. http://abcn.ws/1sGNDo0

IN CASE YOU MISSED IT

MAYOR JULIAN CASTRO TO BE TAPPED AS HUD SECRETARY. San Antonio Mayor Julian Castro will be nominated as secretary of Housing and Urban Development, ABC's JEFF ZELENY reports. The White House declined to comment on the timing of an official announcement. The position must be confirmed by the Senate. The officials said the news was not intended to be disclosed, but apparently it leaked out because Castro's associates in San Antonio received calls from the FBI about a background check. It was first reported in a column in this weekend's San Antonio Express News. Current HUD Secretary Shaun Donovan will likely be tapped to lead the Office of Management and Budget as part of a restructuring in the Cabinet after Kathleen Sebelius stepped down as secretary of HHS. The 39-year-old Castro is a rising star in the Democratic Party. He delivered the keynote address at the party's 2012 convention in Charlotte, N.C. His twin brother, Joaquin, is a Democratic congressman from Texas. http://abcn.ws/1t2lvxL

WHAT WE'RE WATCHING

MARCO RUBIO'S 'POT' HOLE. Why won't Sen. Marco Rubio say whether he's ever smoked pot? The Florida Republican, who maintains a strict stance against the legalization of marijuana, refuses to answer whether he's ever personally smoked it. Rubio told "Politics Confidential" that his silence on the matter is based on his belief that there is no "responsible way to recreationally use marijuana." "If you say that you did, then suddenly there are people out there saying, 'Well, it's not a big deal,'" Rubio told ABC's JONATHAN KARL. "On the other side of it is if you tell people that you didn't, they won't believe you." To hear if he plans to try and run two elections at once, check out this episode of "Politics Confidential." http://yhoo.it/1gZtUdY

WHO'S TWEETING?

@SalenaZitoTrib: My report today on Republican women; they may not only tip power in DC they can also alter party perception http://triblive.com/politics/politicalheadlines/6108202-74/women-party-republican …

@russellberman: Boehner's big decision: He's tied himself in knots on #immigration. Can he untangle himself, & the GOP, by July? http://thehill.com/homenews/house/206447-all-eyes-on-boehner …

@TheFix: So @ktumulty is at the Wake Forest commencement where Jill Abramson will speak this AM. Yet another reason to follow her.

@RollCallAbby: DCCC raised $7.1m in April. Included an Obama Houston fundraiser http://atr.rollcall.com/house-democrats-raise-7-1-million-in-april/ …

?@samyoungman: Weekend before the primary, McConnell focuses his fire on Obama http://www.kentucky.com/2014/05/18/3248259/as-primary-nears-mcconnell-talks.html …