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The press has its own way of defining "winning" at the first Democratic debate in Las Vegas.
In a campaign dominated by Donald Trump and a crowded Republican field, Tuesday night's faceoff will offer Hillary Clinton a chance to overcome months of negative headlines, Bernie Sanders an opportunity to prove he is presidential, and the others on stage some moments to win some much-needed media attention.
But wresting control of the narrative -- creating that viral moment that ricochets across television screens, YouTube, and social media for days and even weeks -- will require shrewd political savvy and a willingness to go on the offensive, especially for the also-rans.
"The Clinton-Sanders dynamic, and the sparks from it, will likely dominate, so 'winning' for the non-front-runners means finding a way into the conversation," Robert Costa, the national political reporter for The Washington Post, told CNN.
"That means understanding how to use your moment, however brief, to rouse those watching," he added.
Susan Page, Washington bureau chief for USA Today, said the debate also is important for candidates to set themselves up for the primary process.
"I don't think the debate is necessarily a zero-sum game," she said. "It's not so much what the contenders need to do to win the debate; it's what they need to do to position themselves to prevail as the nominee."
Mark Leibovich, the New York Times Magazine National Correspondent, said a catchy one-liner could make a difference.
"Since this debate will likely have lower ratings [than the two Republican debates], I'd guess the 'one-liners' and soundbites will carry more weight," Leibovich said. "But, unlike the R's, the combatants will not have to fight tooth and nail for attention, so maybe we can expect a less frantic, more conversational vibe."
Here's a look at what each candidate needs to do to win the news cycle, based on conversations with journalists and pundits.
Hillary Clinton: Her greatest challenge
No candidate enters Tuesday night's debate as cognizant of the media dynamic as Clinton.
For months, she has been portrayed by the press as untrustworthy, inauthentic and out-of-touch, causing her poll numbers to drop by 20 points. In September, she went on a media blitz, in part to convince the American public that she was, in her words, "a real person."
So Clinton's greatest challenger on the debate stage is Clinton.
She needs to overcome her reputation as a scripted political veteran and show some heart and soul, several journalists said. She needs to convince wary Democrats and independents that they should be excited about her campaign. And, of course, she needs to tackle the issue of her use of a private email server.
"A lot of reporters are looking for a great soundbite that addresses the question of trust," Ron Fournier, the National Journal columnist, told CNN. "I think she is underestimating the weight she's put on herself by undermining her credibility with the email scandal."
"There's no doubt that she's an incredible public servant, by far the most prepared debater, and by far the most qualified candidate," he continued. "But there's a lack of credibility and a lack of trust and that could make her vulnerable."
A key part of the evening for media watchers is whether the other candidates go after Clinton and, if they do, how the former secretary of states handles the jabs.
"Clinton will probably get attacked and baited by one of the others...She is accustomed to this, and will be prepared and knows how to handle herself," said Leibovich.
"She just needs to hit her notes, remind everyone that she's a competent and possibly historic figure -- and better than the campaign she has run to this point, not to mention the caricature that her opponents have perpetuated."
Bernie Sanders: A lot to prove
Sanders comes to Vegas with the media momentum.
The national press has been eagerly awaiting the outspoken democratic socialist's first turn on the stage alongside Clinton, and will be looking for drama in a face-off between the two who are leading the field.
"The headlines will be all Hillary-Bernie," said Jon Ralston, the veteran Nevada political reporter, adding that he thought it was "highly unlikely" that other candidates would be able to nab the limelight.
Reporters and pundits said Clinton has to be careful not to let Sanders' passion for his causes steal the moment. But at the same time the risk for Sanders is not coming off as presidential. He's got a chance in Las Vegas to convince the press (and the public) he's up to the Oval Office.
"Bernie Sanders has exceeded nearly everyone's expectations in becoming the hero of Democratic progressives," Page said.
"To go to the next level -- to become not only Hillary Clinton's chief challenger but also a potential nominee -- he needs to expand that appeal to include other important parts of the Democratic coalition, including African Americans, Hispanics and blue-collar workers," she added. "The debate is a forum that gives him an opportunity to reach those voters and make his case."
Like Clinton, Sanders also needs to demonstrate that he's likable. His passion can be inspiring, but it can also be off-putting, some journalists warned. He seems to rail against things -- inequity, the establishment, the media -- as often as he tries to rally support for his causes, risking coming off looking like a cantankerous scold.
For Sanders to win Tuesday's headlines, he may need to deliver a viral moment -- a deft one-liner or a few punches that land on the front-runner. He will need to take advantage of his openings, not just present his policy proposals and attack the system.
Martin O'Malley and the rest: Last chance?
If the media is looking to Clinton and Sanders for fireworks, they're all but ready to ignore O'Malley, Jim Webb and Lincoln Chafee unless they prove otherwise. The media mindset for these three is: Come out swinging or go home forgotten.
Of the group at the back of the pack, O'Malley is expected to bring the most to the stage. For a time, the press had thought he would be Clinton's toughest rival. He's now polling at half-a-percentage point and garners hardly any media attention.
He needs a Carly Fiorina type of night.
"O'Malley has the best shot to [gain momentum] and this is a make-or-break moment for his campaign," Dan Pfeiffer, the former senior adviser to President Barack Obama, told CNN.
"It would require a dominating performance that showed him to be an exciting and electable alternative like Fiorina had in the last GOP debate," he added.