DETROIT — The Democratic Party’s ideological divide was on full display Tuesday night as Bernie Sanders and Elizabeth Warren faced a fusillade of incoming fire from more moderate presidential contenders determined to cast their proposals as too costly and unrealistic and a sure path to reelecting Donald Trump.

Warren and Sanders fended off one blitz after another from low-polling centrists who repeatedly derided their government-heavy policies as “fairy tale” wish lists that would alienate swing voters, limit Americans’ freedoms and inevitably raise taxes on the middle class.

Montana Gov. Steve Bullock, who was appearing on the debate stage for the first time, assailed Warren’s and Sanders’ support for “Medicare for All,” a plan he and former Rep. John Delaney of Maryland faulted for abandoning Obamacare and eliminating many Americans’ private insurance plans.

“At the end of the day, I won’t support any plan that rips away health care from individuals,” Bullock said, noting his success as a Democrat in a red state Trump carried. “This is an example of wish-list economics. It used to be Republicans that wanted to repeal and replace; now many Democrats do as well.”

Sen. Amy Klobuchar of Minnesota, who is fighting to keep her campaign alive, tried to provide a voice of reason – as well as moderation.

“We are more worried about winning an argument than winning an election,” she said in an apparent reference to a number of liberal proposals that would never pass a GOP-controlled Senate, such as Medicare for All, the Green New Deal and decriminalizing all border crossings.

But Warren and Sanders stood their ground, unapologetically defending their proposals while making the case for a broad restructuring of the country’s health care, immigration and environmental policies as the best way to stir voters’ passions and rally them to their side.

Warren and Sanders accused the other Democrats on stage – and one of the CNN moderators -- of taking up Republican talking points when they worry about the fallout from Medicare for All plans, including the loss of private insurance plans that so many Americans have and like.

“I don’t understand why anybody goes to all the trouble of running for president of the United States to talk about what we really can’t do and shouldn’t fight for. I don’t get it,” the Massachusetts senator said in response to Delaney. “…We need to have the courage to fight back against that, and until we're ready to do that, it's just more of the same. Well, I'm ready to get in this fight. I'm ready to win this fight."

Sanders, who appeared to have formed a non-aggression pact with Warren, wholeheartedly agreed.

"To win this election and to defeat Donald Trump – which, by the way, in my view is not going to be easy -- we need to have a campaign of energy and excitement and of vision. We need to bring millions of young people into the political process in a way that we have never seen by, among other things, making public colleges and universities tuition free and canceling student debt."

Winner: Elizabeth Warren

Warren walked on as one of two heavyweights, an obvious target of attack for candidates polling in the single digits and below. What came next was a debate between the progressives and the centrists who bemoaned big-government policy proposals as unrealistic and, therefore, a boon to Trump’s reelection.

Warren didn’t throw up her hands, didn’t shout at opponents and didn’t flinch for the better part of 2 ½ hours.

When Delaney mixed it up with Sanders, her ideological double and closest competition, it was Warren who got the better of the two men. She stepped into the argument to chide the former Maryland congressman for doubting the policy.

He said Medicare for All was “political suicide.” She said he was regurgitating “Republican talking points.”

“Let's be clear about this: We are the Democrats. We are not about trying to take away health care from anyone,” Warren argued. “That's what the Republicans are trying to do.”

The onslaught against the progressive vision continued, and while Sanders got visibly flustered, Warren remained stern, energized and composed. After multiple swipes from the candidates on both sides of her, the Massachusetts liberal dug in.

“I don’t understand,” she said with amusement, “why anybody goes to all the trouble of running for president of the United States just to talk about what we really can’t do and shouldn’t fight for.”

Warren may have built on her momentum, an argument her campaign made in the spin room afterward. Only polling can prove that argument, but there is one immediate and indisputable takeaway: She ran the board. Warren made her case for 18 minutes 33 seconds, more time than any of the other candidates auditioning on stage.

Winner: Steve Bullock

First impressions matter, and that was doubly true for Bullock, who didn’t qualify for the first debate and who doesn't enjoy national name recognition. He had a good night.

While Warren and Sanders championed the progressive cause, Bullock was the strongest of the dissenting centrists.

“I'm a pro-union, pro-choice, progressive Democrat who won three elections in a red state, not by compromising, but by getting stuff done," Bullock said in his opening remarks. "That's how we win back the places we lost -- by showing up, listening and focusing on the challenges of everyday Americans.”

It was an overture to those voters who worry that Democrats have put themselves on shaky footing by moving too far to the left too quickly. Bullock had the pre-packaged buzzwords to drive that point. Medicare for All? In his words, it is more “wish-list economics.”

Extending Medicare to every citizen by default meant “disrupting” the private health care of millions of Americans as a result.

“At the end of the day, I'm not going to support a plan that rips away quality health care from individuals. This is an example of wish-list economics," Bullock said. "It used to be Republicans that want to repeal and replace. Now, many Democrats want to as well.”

On the immigration front, Bullock was also prepared. Other candidates want to decriminalize border crossings. To push back, the governor, a former state attorney general, invoked the last Democratic administration.

“A sane immigration system needs a sane leader. And we can do that without decriminalizing and providing health care for everyone," Bullock said. "And that's not me saying that, that's Obama's Homeland Security secretary.”

Bullock mixed it up with Sanders and with Warren, laughing off a mispronunciation gaffe, all the while displaying a cool, steady oratory and command of the issues. His challenge now is staying in the conversation by qualifying for the next debate in September.

Winner: John Delaney

His own campaign reportedly tried convincing him to drop out. His case hasn’t won over more than 1% of voters, according to the RealClearPolitics polling average. His candidacy has been the subject of multiple obituaries. All the same, Delaney was a winner Tuesday night.

The oratory and the polish of the former congressman didn’t make him stand out. CNN did. Rather than using Trump as a foil, the moderators made Delaney part of the conversation.

Delaney has kept his campaign moving forward by taking constant shots at the likes of Warren and Sanders over their respective versions of Medicare for All. Prodded by the moderators, the progressives responded directly, knocking him around but elevating him all the same.

This gave the former health care executive time to make his case.

“When we created Social Security, we didn't say pensions were illegal, right? We can have big ideas to transform lives,” he said before labeling himself “as big of a dreamer and an entrepreneur as anyone.”

“But I also believe we need to have solutions that are workable. Can you imagine if we tried to start Social Security now but said private pensions are illegal?” he asked.

“That's the equivalent of what Sen. Sanders and Sen. Warren are proposing with health care. That's not a big idea. That's an idea that's dead on arrival,” he concluded.

If voters find his case persuasive, Delaney might get a much-needed boost. It is something he didn’t get at the last debate in Miami. Farther north in Detroit and one month later, the long shot at least got a shot. Knowing it might be his last, he did his best.

Loser: Bernie Sanders

Warren’s Tuesday night strength inevitably takes some wind out of Sanders’ sails. The two may have appeared as a like-minded tag team, but the fact is they share the same policy positions and liberal base of voters so her rise inevitably involves at least a little sinking on his end.

The other parts of the equation amount to style points for Warren. She delivered an impassioned argument for Democrats to remain true to their hearts and their trust in government to solve the nation’s problems, and she did so in clear, emotional and policy-oriented terms without getting ruffled and losing her composure.

Sanders, in contrast, was agitated and bellowing from the onset. He defended the potential impact of his signature health care proposal from attacks by more moderate Democratic candidates by angrily declaring he knows the issue best, because, after all, “I wrote the damn bill.”

Sanders’ irascible temperament was a fresh contrast to Hillary Clinton’s heavily rehearsed, often robotic appearances in 2016. By now, however, voters are quite familiar with Sanders’ angry socialist insurgency, which appears to have lost some of its firepower if audience responses and after-debate cable news spin is any indication.

At one point, Rep. Tim Ryan of Ohio questioned whether Sanders’ Medicare for All plan would be as good as the benefits union members fought to negotiate. Roughly 600,000 union workers in Michigan alone would be forced to give up their private insurance, moderator Jake Tapper noted.

Sanders then appeared overly exasperated, lacing into Tapper for using a “Republican talking point” and pointing out that the health care industry is advertising during CNN’s debate coverage.

“Thank you, senator. Senator Warren, it’s your turn,” Tapper interjected. “Your time is up.”

But Sanders was undeterred, continuing to go after the moderator and the cable network hosting the debate. “They will be advertising tonight with that talking point,” Sanders jabbed.

At one point, former Colorado Gov. John Hickenlooper ridiculed Sanders’ exasperation. When the Vermont senator threw up his hands in reacting to Hickenlooper characterizing his Medicare for All as “radical changes,” Hickenlooper appeared to roll his eyes.

“Throw your hands up!” he snapped.

“Okay,” Sanders said, repeating the gesture. Hickenlooper than openly mocked him, throwing up his hands too.

Loser: Beto O’Rourke

While Sanders will continue to enjoy strong nationwide support from a movement he built in 2016, O’Rourke doesn’t have that luxury.

The former Texas congressman, who gave Sen. Ted Cruz a run for his money in 2018, had the most riding on this debate. But he failed to deliver a real break-out moment to help re-energize his campaign, which has been flagging in recent months after a launch earlier this year accompanied by much media fanfare and donor enthusiasm.

O’Rourke lost ground during the first debate when former San Antonio Mayor Julian Castro appeared to have more knowledge about how best to handle the country’s immigration problems despite both men hailing from a border state where the crisis is unfolding.

Tuesday, he was hoping to resuscitate his campaign or steal thunder back from Indiana Mayor Pete Buttigieg, who has replaced him as the brightest rising star in the Democratic field.

O’Rourke logged less than 11 minutes of talk time during the prime-time television event that lasted nearly three hours and was largely dominated by Warren and her series of attacks on Wall Street and corporate America. His best applause came near the debate’s end when he stressed the need for taxpayer-funded slavery reparations for African Americans.

“[The legacy] of slavery and segregation and Jim Crow and suppression is alive and well in every aspect in the economy and the country,” he said. “As president … I will sign into law Sheila Jackson Lee’s reparations bill, so we can have the national conversation we waited too long in this country to have.”

O’Rourke, whose support is hovering just under 3% in the RCP poll average, has already qualified for the next round of debates so there’s still hope yet. The fall debate will bring another chance for Texas Democrat to land some punches.

Loser: Amy Klobuchar

Still polling just above 1%, the Minnesota senator desperately needed to emerge from the second debates with a surge of momentum. While she logged a lot of talk time, the very strengths she has brought to the Senate and the campaign – a pragmatic streak to an otherwise solidly liberal record – appeared to hold her back on Tuesday night.

She politely hammered Warren and Sanders -- without naming them -- over the need to moderate their liberal proposals, especially when it comes to health care, and seemed content to train her fire on Trump.

“Let’s get real,” she said in her opening statement. “Tonight we debate, but ultimately we have to beat Donald Trump.”

The points were salient, but the three-term senator still managed to came across as nervous, canned and less passionate than the other moderates, even as she criticized Trump’s “racist attacks.”

“We come from a country of shared dreams. And I have had it with the racist attacks,” she said.

But her policy-heavy answers and pleas for candidates to move to the center often failed to connect with audience members. Polls will show whether she boosted her support among swing voters, one of her stated goals.

“There are people that voted for Donald Trump that weren’t racist, they just wanted a better shake with the economy,” she said. “I will appeal to them.”