LAS VEGAS — (CNN)  It was a victorious comeback for Hillary Clinton, a front-runner who has been on the downswing.

The former secretary of state and first lady, who once came within a few cracks of shattering the glass ceiling to win a major party’s presidential nomination, stepped on to a debate stage once more Tuesday night. But this time, it was to ask the American people to allow her to succeed the very man who had crushed her White House dreams seven years ago.

In the first Democratic debate of the 2016 cycle hosted by CNN and Facebook in Las Vegas, Clinton faced off against four others trying to make the same case. But it was only the rival standing to Clinton’s immediate right — Vermont Sen. Bernie Sanders, whose insurgent call for a political revolution has electrified the liberal base — that shared her spotlight.

Here are CNN’s key takeaways:

The return of the favorite (She’s back)

Hillary Clinton hadn’t set foot on a national debate stage in seven years.

But far from seeming out of practice, it appeared as though she had been preparing for Tuesday night since her last failed White House bid.

For more than two hours, the Democratic front-runner showed off the very skills that made her so formidable in the more than the two dozen debates she participated in ahead of the 2008 election, offering crisp, confident and fluent answers on a wide range of policy issues.

Challenged on whether she is a progressive or a moderate, Clinton sought to link herself with the liberal wing Bernie Sanders represents without getting too attached to his brand of democratic socialism.
“I’m a progressive,” Clinton responded. “But I’m a progressive who likes to get things done.”

More than anyone else on stage, it was Sanders that Clinton used most willingly to show off her dexterity. Given her first opportunity to take a jab at the Vermont senator, Clinton didn’t miss a beat.

“No. Not at all,” Clinton responded when asked whether Sanders has been tough enough on guns.

Later, when Sanders remarked that he doesn’t support American troops in Syria, Clinton interrupted. “Well, nobody does,” she said. “Nobody does, Sen. Sanders.”

Clinton also seemed to want to tackle a major criticism that dogged her candidacy seven years ago: that she can come across as robotic and cold. She kicked off the debate by invoking her family — “I’m the granddaughter of a factory worker and the grandmother of a wonderful one-year-old child,” she said — and ended the debate with a reference to her late mother.

She also brought up her gender, noting twice that she’d be the first woman President. And during a high point for the audience, she lambasted Republicans for targeting Planned Parenthood and offered a crisp defense of the embattled organization.

A different stage for Bernie

Sanders on the debate stage is a different ballgame than a Bernie rally.

Yes, he brought his style — which means he yelled, he gesticulated and he played the role of explainer. But the debate hall was more sedate than his massive rallies, and the intrusion of his opponents and the moderators placed a reality check on what Sanders prefers – a stream of conscious lecture.

Sanders promised to explain Democratic socialism to America and pointed admiringly to Nordic countries for their liberalism. But while the praise of Denmark might work in New Hampshire, on the debate stage in Nevada, Clinton reminded him that this is America.

On guns, he seemed unprepared for a challenge from Clinton that he should have known was coming. It’s an issue where his record has been at odds with the liberals who are fueling his campaign. And Jim Webb subtly challenged him when he said that the revolution Sanders is waiting for wasn’t going to happen and Congress wouldn’t pay for his agenda.

His best moment was when he decided enough was enough with the talk of Clinton’s private email server as Secretary of State, underscoring her argument that people “are sick and tired of your damn e-mails.” It was a moment of humor laced with Sanders trademark fire. But it was also a reminder that if he is to grow as a candidate, Sanders will need Clinton’s voters.

Democrats stick to the Reagan Rule

For the viewers who were hoping for mudslinging and finger-pointing, what they got Tuesday night was more like a session of Model U.N.

Though the Democratic candidates on stage at times disagreed on politically sensitive issues including gun control, the Iraq War and Wall Street regulations, the sharp personal attacks that dominated the Republican debates were nowhere to be seen.

Lincoln Chafee came closest to making an allegation about personal integrity, saying to Clinton: “We need someone that has the best in ethical standards as our next president.”

Ronald Reagan’s famous 11th Commandment was: Do not speak ill of fellow Republicans. Republicans, prodded by Donald Trump, have broken the commandment again and again in this election cycle.

But at this debate, Democrats followed Reagan’s rule and were nice to each other, saving their most stinging criticisms of the night for the GOP — particularly Trump.

O’Malley, who referred to Trump as “that carnival barker in the Republican Party,” said the first Democratic fight night only helped cast the GOP in an unflattering light.

“In this stage, you didn’t hear anyone denigrate women, you didn’t hear anyone make racist comments about new American immigrants, you didn’t hear anyone speak ill of another American because of their religious beliefs,” O’Malley said, in apparent reference to Trump’s inflammatory remarks about women and immigrants and retired neurosurgeon Ben Carson’s comment that he would not want a Muslim-American to serve in the White House.

Hillary Clinton is more hawkish than her party

Clinton is to the right of her party on foreign policy — but she’s faced this type of challenge before.

Obama hammered Clinton constantly for her vote to go to war in Iraq during the 2008 campaign. And Chafee tried that line of attack Tuesday, suggesting that her vote disqualified her from the White House.

Her response stopped the line of questioning cold. “Well, I recall very well being on a debate stage, I think, about 25 times with then Senator Obama, debating this very issue,” Clinton said. “After the election, he asked me to become Secretary of State. He valued my judgment, and I spent a lot of time with him.”

Sanders took a veiled swipe at Clinton by calling the Iraq war, “the worst foreign policy blunder in the history of this country.” And he said he doesn’t want a repeat in Syria, where “you’re talking about a quagmire in a quagmire.”

Both Sanders and O’Malley hit Clinton for advocating a no-fly zone in the midst of Syria’s refugee crisis, with O’Malley calling it a “military tool” he wouldn’t use.

Clinton, though, advocated a stronger U.S. role in ending the civil war in Syria — and particularly in limiting Russia’s influence and stopping Russian President Vladimir Putin’s “bullying.”

“I think it’s important too that the United States make it very clear to Putin that it’s not acceptable for him to be in Syria creating more chaos, bombing people on behalf of Assad, and we can’t do that if we don’t take more of a leadership position, which is what I’m advocating,” she said.

Clinton didn’t offer a specific nation, group or leader when asked about the country’s biggest foreign policy threat, instead pointing to the threat of nuclear weapons and terrorists who are seeking them.

Clinton’s flip-flops

Clinton’s shifting position on everything from the Trans Pacific Partnership trade deal to gay marriage followed her onto the debate stage and were the subject of pointed questions by Anderson Cooper. She stuck to a familiar script Tuesday, but there’s only so far that can get her.

Clinton has come under pressure since announcing her White House bid to explain what critics have billed flip-flops, and she has consistently maintained that her views always evolved after learning more about a given issue.

“I’ve been very consistent over the course of my entire life,” Clinton answered when asked whether she was willing to say anything to get elected.

On her recent about face on the Trans-Pacific Partnership— she came out against it last week after having referred to it as the “gold standard” of trade deals as secretary state — Clinton said she had “hoped it would be the gold standard,” and only recently decided that it in fact, was not. “It was just finally negotiated last week, and in looking at it, it didn’t meet my standards,” she said.

But it was her answer to why she took so long to oppose the Keystone pipeline that could cause headaches for the former secretary of state down the line. “I never took a position on Keystone until I took a position on Keystone,” Clinton said.

The response is the perfect one-liner for GOP ad makers looking to make the case that Clinton has a pattern of changing her mind for political expediency.

The other guys

The undercards couldn’t seem more out of place on the debate stage.

There were moments of exceptions — particularly for Martin O’Malley who gave a strong closing argument —but the former Maryland governor failed to make a memorable case for his candidacy or draw distinctions with Sanders or Clinton. He had an opportunity to make an impression, and failed to take advantage.

Chafee had perhaps the most cringe-worthy moment of the night. Asked about his 1999 vote to repeal Glass-Steagall, the Depression-era law that blocked commercial banks from engaging in investment banking, blamed his vote on the fact he was a rookie in office. That didn’t fly, and challenged twice to justify his vote, he finally cracked.

“I think you’re being a little rough,” the former Rhode Island senator and governor said. “I’d just arrived at the United States Senate. I’d been mayor of my city. My dad had died. I’d been appointed by the governor. It was the first vote and it was 90-5, because it was a conference report.”

Webb used his limited time to complain that he didn’t have enough time — four times he complained to moderator Anderson Cooper that he had waited 10 minutes to speak, rather than going on the offense or lay out his own vision. With a sparse campaign schedule and little rationale for his candidacy, it’s hard to see him ending up in future debates as he didn’t add much.

Cooper, tired of Webb’s complaints about speaking time, summed it up: “You agreed to these rules and you’re wasting time. So if you would finish your answer, we’ll move on.”

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