Democrats in night 2 of 2nd presidential debate tackle health care, Trump, immigration, climate

Night two of the Democrats' second set of presidential primary debates in Detroit featured former Vice President Joe Biden flanked by California Senator Kamala Harris and New Jersey Senator Cory Booker.

During the opening moments of the debate, Biden and Harris clashed over their dueling health care plans. 

Harris, one of Biden's chief rivals, said her proposal would extend health insurance to all Americans, while Biden's would "leave out" almost 10 million.

Biden criticized Medicare-for-All backers as he argued for his “public option” proposal to expand the Affordable Care Act without ending job-based insurance. 

Biden said Harris’ plan is too expensive and would cause many people to lose their current, employer-based health insurance. 

The former vice president said he doesn't "know what kind of math you do in New York" or "in California" as he pointed to estimates that single-payer insurance could cost about $30 trillion over 10 years.

He said Harris isn't being straight about that, adding, "You can't beat President Trump with double-talk."

Harris said Biden is "simply inaccurate," noting private insurers' billions of dollars in profits.

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Single-payer supporters note that their approach would replace Americans' premium and out-of-pocket costs for private insurance. Harris also insisted her pitch would not require middle-class tax increases.

Colorado Sen. Michael Bennet also went after Harris on health care, suggesting she hasn't been upfront about planks of her Medicare for all plan.

Bennet charged that the plan would mean a tax increase for the middle class and outlaw private insurance, and told Harris that "we need to be honest about what's in this plan.“

Harris released details of her health care plan earlier this week. It would allow private Medicare plans that follow certain federal guidelines, and it would include a tax on household income over $100,000.

Harris accused Bennet of using "Republican talking points" and defended her plan by insisting it doesn't make anything illegal, but rather "separates the employer from health care."

President Donald Trump and some of the leading Democratic presidential candidates were also the targets of opening statements.

Bennet said Trump "frankly doesn't give a damn about your kids or mine."

Harris repeated her pledge to "prosecute the case" against Trump, while Biden stuck to his promise to "restore the soul of this country" after four years of Trump.

Diversity was also an early focus.

Biden said Trump was tearing at the "fabric of America" and highlighted the value of diversity in his opening statement."Mr. President, this is America," Biden said of the diverse slate of candidates on stage.

Harris also referenced to what she called a divisive presidency.

"This becomes a moment we must fight for the best of who we are," Harris said. "We are better than this.“

Washington Gov. Jay Inslee was the first candidate on Wednesday's debate stage to call Trump a racist. "We can no longer allow a white nationalist to be in the White House," Inslee said. 

Former Obama administration housing secretary Julian Castro was the second Democratic presidential candidate in Wednesday's debate to explicitly label Trump a "racist."

Sen. Kirsten Gillibrand said she feels responsibility as "a white woman" to challenge institutional racism. She said it's not just up to the two leading black candidates, Sens. Kamala Harris and Cory Booker, to talk about race.

Democrats and some Republicans have criticized Trump in recent weeks for using Twitter to say four Democratic women in Congress should "go back" to their countries of origin. All four are U.S. citizens, and three were born in the country. Trump fired back, declaring himself “the least racist person” on Tuesday.

Harris said Trump "needs to be held accountable" for what she sees as 10 prosecutable offenses in special counsel Robert Mueller's report on Russian interference in the 2016 election.

In the opening moments of the debate, New Jersey Sen. Cory Booker was forced to pause for hecklers shouting "fire Pantaleo," a reference to the New York City police officer officials opted not to charge in the death of Eric Garner. New York City Mayor Bill de Blasio was also confronted directly on the issue by Castro and Gillibrand, who both said that Pantaleo should have been fired.

Over immigration policies, Biden and Castro clashed.

Castro has promised to make illegally crossing the U.S.-Mexico border punishable by a civil penalty instead of a criminal charge and repeated that call Wednesday. He said that doesn't mean endorsing "open borders," but said some in his party, including some on the debate stage, have "taken the bait" and fallen for a Republican talking point.

Biden said he doesn't support decriminalizing such border crossings, adding that he never heard Castro "talk about any of this while he was secretary.“

"It looks like one of us has learned the lessons of the past and one of us hasn't," Castro responded.

Biden has also distanced himself from a trade deal that was a centerpiece of the Obama administration. He said that he would "renegotiate" the Trans-Pacific Partnership but not simply rejoin the pact "as it was initially put forward.“

Trump pulled out of the Obama-era deal two years ago.

De Blasio noted that then-Sen. Biden supported the original NAFTA trade deal, and challenged Biden on a new Trump proposal he termed "NAFTA 2.0."

That led to a back-and-forth with Biden, whom de Blasio has previously called “out of touch.”

"We believe in redemption in this party," de Blasio said. Biden replied, "Well, I hope you're part of it."

The Democratic presidential candidates had theories about why Trump won the Midwest and how they can take it away from him in 2020.

Biden reminded the Detroit debate audience that he helped implement bills during the Great Recession that helped bail out General Motors.

Booker said Michigan, Pennsylvania and Wisconsin were lost because of Russian meddling and Republican suppression of black votes. He said he'd prioritize nonwhite voters to flip those states.

Gillibrand noted her electoral success in upstate New York to prove she can reach swing voters.

Entrepreneur Andrew Yang said winning requires making a case to Midwesterners that the growing economy "has left them behind."

Gillibrand said engaging with climate change will be her top priority if elected president — but the first thing she'll do if elected is "Clorox the Oval office."

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The Democratic candidates largely agreed on the overall goal of addressing climate change but differed in degrees of urgency.

Inslee said Biden's climate plan doesn't move the nation fast enough off of fossil fuels. He said "middle-ground solutions like the vice president has proposed... are not going to save us. Too little, too late is too dangerous.“

Biden said he is committed to re-engaging the international community on combating climate change and re-joining the Paris Climate Accord.

While Biden took many hits on the stage, there were multiple opponents aiming for Harris as well. Hawaii Rep. Tulsi Gabbard tore into Harris' record as a prosecutor and attorney general in California.

Prior to Wednesday night’s debate, Biden's team said that he hoped to focus his attacks on Trump but that he was ready to fight back more aggressively against Harris and Booker if provoked.

Biden also promised he'd counter more aggressively than he did in the June debate in Miami.

Harris hammered Biden in that opening round for opposing federal busing orders issued in the 1970s to desegregate public schools like hers in California.

Booker has blasted Biden for helping write a 1994 law blamed for accelerating mass incarceration.

The former vice president, who leads virtually all early polls, is considered the premier moderate on stage. In addition to Harris and Booker, his more progressive opponents include de Blasio, Gillibrand, Inslee, Castro, Yang and Gabbard. 

While the first primary votes won't come for six more months, there is a sense of urgency for the lower-tier candidates to break out. More than half the field could be blocked from the next round of debates altogether — and possibly pushed out of the race — if they fail to reach new polling and fundraising thresholds implemented by the Democratic National Committee.

The dire stakes have forced many Democrats to turn away from Trump and turn against one another in recent weeks.

Fox TV Stations' Gabrielle Moreira and the Associated Press contributed to this report.