LAS VEGAS (CBSNewYork/AP) — Hillary Rodham Clinton and Bernie Sanders sparred on policy positions — but sometimes came out in agreement — as the 2016 Democratic presidential candidates held their first debate Tuesday night.

Sanders, the rumpled independent senator from Vermont and a self-described democratic socialist calling for “political revolution,” has become a surprise arch-rival for Clinton.

Early on in the debate, moderator Anderson Cooper asked Sanders about his self-description as a Democratic Socialist, noting that it is a term that could be used against him by opponents.

Sanders said more people would support the concept of Democratic Socialism if they understood what it was.

“We’re going to explain what Democratic Socialism is, what Democratic Socialism is about, and what Democratic socialism is about is saying that it is immoral and wrong that the top one tenth of 1 percent in this country owns almost as much wealth as the bottom 90 percent,” Sanders said.

When asked if he was a “capitalist,” Sanders said he did not consider himself part of the “casino capitalism process” that includes Wall Street and the wealthiest Americans.

Clinton responded that she thinks what Sanders said “makes sense in terms of the inequality that we have, but we are not Denmark.”

She said capitalism should be supported in the form of small businesses that Americans have the freedom to start, and the real need was to rein in excesses and “save capitalism from itself.”

Meanwhile, Clinton was asked about her reputation in some quarters for flip-flopping on issues.

She responded: “I have always been for the same values and principles, but like most human beings, I do absorb new information. I do look at what’s happening in the world.”

When asked if she was a progressive or a moderate, she responded: “I’m a progressive, but I’m a progressive who likes to get things done. I know how to find common ground and I know how to stand my ground.”

But while Sanders has been considered farthest to the left among the candidates, some of the other candidates took him to task for siding with the political right on some issues with regard to gun control. Clinton noted that he voted against the Brady Bill five times, and also voted in favor of allowing guns to be carried on Amtrak trains.

Sanders said he supported “strong common-sense gun legislation,” but emphasized that he represents a rural state and must take that into account in his support for gun control.

Candidate Martin O’Malley, a former Maryland governor, shot back saying the issue of gun control is “not about rural and urban.” He noted that the Maryland gun control policy enacted on his watch still managed to preserve the interest of hunters and many other firearm users.

Sanders came to Clinton’s defense when it came to the controversy about her use of a private server for work-related emails when she was Secretary of State.

Noting that committee investigating the controversy has spent $4 1/2 million of taxpayer money, the country should really be talking “not about my emails, but about what people want from the President of the United States.”

Sanders said, “I think the Secretary of State is right, and that is that the American people are sick and tired of hearing about the damn emails.”

But fellow candidate Lincoln Chafee was not so forgiving.

“We have to repair American credibility after we told the world that Saddam Hussein had weapons of mass destruction, which he didn’t,” Chafee said, adding that the email controversy could call Clinton’s credibility into question.

When asked if she wanted to respond, Clinton simply said, “No.”

The candidates were also asked a question on video by a student, who asked whether they support the statement, “black lives matter,” or the statement “all lives matter.”

The expression “black lives matter,” has been a rallying cry during protests over the deaths of African-Americans at the hands of police. The activist movement has come to be known as the Black Lives Matter movement.

Many critics have said the expression “all lives matter” comes off as an attempt to detract attention away from institutional racism.

Sanders replied: “Black lives matter, and the reason those lives matter is the African-American community know that on any given day, some innocent person like Sandra Bland can get into a car and three days later, she’s going to end up dead or in jail.”

O’Malley was criticized previously for saying, “Black lives matter, white lives matter, all lives matter.” But this time, he said, “The point is that the Black Lives Matter is making is a very, very serious and legitimate point” and the country has “undervalued” black lives.

Earlierm Chafee was asked about the fact that he changed parties from Republican to Independent and finally to Democrat.

Chafee replied that he began as a liberal Republican and changed parties over time, but said, “I have not changed on the issues.”

“You’re looking at a block of granite when it comes to the issues,” Chafee said. Of the GOP, he added: “The party left me. There’s no doubt about that.”

Also on the podium were former Virginia Sen. Jim Webb, a decorated Vietnam veteran who criticized Clinton for her early support of the Iraq War.

Webb was asked about his contention that affirmative action can be discriminatory against whites – which Cooper said could present him as out of touch with his party.

Webb said he believes the Democratic Party “gives people who otherwise have no voice in the corridors of power a voice, and that is not determined by race.” He said he has always supported affirmative action for African-Americans given the history of slavery and Jim Crow laws. But he called “creating diversity programs including everyone of color” while excluding struggling whites such as Appalachians “not true to (Democrats’) principles.”

Webb was also asked whether he was out of step as a backer of coal and the Keystone pipeline. He responded that he was supportive of other means of energy production such as nuclear, and that other nations such as China and India must be acknowledged for their role in pollution.

“We are not going to solve climate change simply with the laws here,” Webb said.

Clinton agreed that action against climate change depends on whether “China and India join with the rest of the world.”

The candidates were also asked about such issues as the civil war in Syria, the use of military force overseas, and their votes on the Iraq War in 2003, as well as the DREAM Act and immigration.

Clinton said she would “take more of a leadership position” and stand up to Russian President Vladimir Putin over Syria.

Asked about Russia’s increasing involvement in the Syrian civil war, Clinton says she would take a harder line against Putin. She said, “we have to stand up to his bullying” and “make clear” that Russia has to be part of the solution.

Clinton’s comments were her first criticism during the debate of her former boss, President Barack Obama.

Clinton also says she would create “safe zones” to try to ease the massive refugee crisis destabilizing the region.

The Democratic primary has lacked the drama of the Republican contest and the unexpected rise of Donald Trump. Debate host CNN has already said it expects significantly lower ratings for Tuesday’s debate than the Republican contest the cable channel hosted in late September, which drew an audience of 23 million.

Still, the debate was the largest audience for Democratic candidates since the primary race began. It’s one of six debates the Democratic National Committee has sanctioned, a point of contention among some candidates seeking more nationally televised events to generate much needed attention.

Leading the push for more debates was O’Malley, who has been sharply critical of what he sees as Clinton’s flip-flopping on policy and has also said questions about her email use are legitimate.

As CBS2 Political Reporter Marcia Kramer reported, there were two elephants in the room during the debate. First was Vice President Joe Biden, who has yet to announce whether he will run.

Meanwhile, Republican frontrunner Donald Trump – who was mentioned unflatteringly several times by the Democratic candidates — live-tweeted the debate. He said, “Sorry there is no star on the stage tonight,” and, “The hardest thing Clinton has to do is defend her bad decision-making, including her Iraq vote, emails, etc.”

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