DETROIT — The first night of the second 2020 Democratic presidential debate immediately exposed an ideological rift in the crowded primary field as progressives Bernie Sanders and Elizabeth Warren found themselves under attack from all sides on health care.

The stark ideological divisions among the candidates was a theme that ran through the evening, also cutting across immigration and climate change and the Green New Deal and how to defeat President Donald Trump.

Trump himself remained silent on Twitter throughout the debate, not tweeting, though his campaign put out a short statement after it concluded saying, "Same radical Democrats. Same big government socialist message."

Sanders and Warren, whose strong position in the polls put them center stage at this city's historic Fox Theatre in the CNN-hosted event, are vying with each other to consolidate support on the left, but they notably refused moderators' attempts to get them to engage in highlighting any contrasts between.

Both support "Medicare for All," which would replace private insurance with a government-run system.

But the other candidates on the stage, who all favor more incremental reform that would keep private coverage while adding a new public plan as an option, opened fire on the Vermont and Massachusetts senators.

Beto O'Rourke said there was no need to be "talking about taking away peoples’ choice"; Rep. Tim Ryan of Ohio said Sanders and Warren would eliminate Detroit autoworkers' generous healthcare plans negotiated by their union; and Minnesota Sen. Amy Klobuchar noted Sanders has co-sponsored public option bills in the past, even as he criticizes the idea today for not going far enough.

"We can go down the road that Senator Sanders and Senator Warren want to take us, which is with bad policies like Medicare for all, free everything and impossible promises that will turn off independent voters and get Trump re-elected," said former Maryland Rep. John Delaney, who has spent millions of dollars of his own money on his campaign.

Meanwhile, newcomer Steve Bullock, the more moderate governor of Montana, who missed out on the first face-off in Miami, dismissed their ideas as "wishlist economics," while John Hickenlooper, the former governor of Colorado, said "massive government expansions" would not help.

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Later in the debate, Warren addressed the attacks to cheers: "I don’t know why anyone goes through the trouble of running for president to tell us what we can’t do and what we shouldn’t fight for."

"I am not afraid. And for Democrats to win, you can’t be afraid," Warren said, saying her party can't win "with small ideas and spinelessness."

And Sanders had little patience for the criticism.

"You’re wrong," he said to Delaney, before quipping to the former health care executive that he probably made money off the system. "I do know it — I wrote the damn bill," Sanders hit back after Ryan suggested Sanders didn't understand the consequences of Medicare for All.

And to moderator Jake Tapper of CNN, Sanders snapped, "Jake, your question is a Republican talking point."

The discussion moved on to other issues, like immigration, but the divide persisted.

Bullock said Warren was "playing into Donald Trump's hands" by calling for decriminalizing unauthorized border crossings and warned that liberals' call for providing more services to migrants would only be a draw for them.

"We've got 100,000 people showing up at the border right now. If we decriminalize entry, if we give health care to everyone, we’ll have multiples of that," Bullock said.

Hickenlooper said if the Democratic nominee supports radical ideas like a federal jobs guarantee and the Green New Deal it will be a "disaster at the ballot box — we might as well FedEx the election to Donald Trump."

Bullock, who took the stage spot vacated by Rep. Eric Swalwell of California, who dropped out of the race earlier this month, used it to command much of the debate as he sparred with the senator he called "Bernie."

Ryan, too, found a place for himself on stage after largely disappearing in the first debate, sticking up for workers in his blue-collar district in Youngstown, Ohio, who, as he often says, "shower after work instead of before it.

"You don't have to yell," Ryan said, casually brushing off a blow from Sanders.

O'Rourke and Buttigieg, whose campaigns have both lost some steam after strong starts, had a more difficult time finding their place on the polarized debate stage as they labored to rise above the fray and stake out a rhetorical middle ground.

"It's time to stop worrying what the Republicans will say," Buttigieg said. "Let's just stand up for the right policy."

By a fluke of the draw used to determine the lineup, Tuesday night's stage featured 10 white candidates in a majority-black city, while the five minority candidates in the 2020 Democratic race will go toe to toe on the second night of the debate Wednesday, along with Joe Biden, the front-runner in the polls.

It came amid the furor ignited by Trump after he repeatedly attacked the city of Baltimore and its Democratic representative in Congress, Elijah Cummings, along with four female congresswomen of color, in terms many viewed as racially coded.

"President Trump's racism doesn't just offend our sensibilities. It is changing this country. Hate crimes are on the rise, every single one of the last three years," O'Rourke said.

In calling for further exploration of slavery reparations, O'Rourke went on to say "the way we became the greatest country on the face of the planet was literally on the backs of those who were kidnapped and brought here by force," adding, "The legacy of slavery and Jim Crow is alive and well."

But Klobuchar made a point of noting that while Democrats were right to attack Trump, they also should be careful not to paint all of his supporters with a broad brush.

"There are people that voted for Donald Trump before that aren't racist, they wanted a better shake in the economy, and so I would appeal to them," said Klobuchar, who won reelection in Minnesota by a wide margin on the same night Trump nearly won her state in 2016.

The Detroit debate may be one of the last chances for a number of low-polling candidates to have a breakout moment before the bar to qualify for the next debate in September gets raised significantly, which is expected to winnow the field.

For her part, author and spiritual adviser Marianne Williamson warned Democrats they need to confront a bigger problem than even the most detailed plans in the world can address.

"If you think any of this wonkiness is going to deal with this dark psychic force of the collectivized hatred that this president is bringing up in this country, then I'm afraid that the Democrats are going to see some very dark days," she said to applause from the audience.