Coverage on this live blog has ended. Check out CNBC's recap here.
All times below are in Eastern time.
Bernie Sanders' national surrogate, Phillip Agnew, declared something like victory at the campaign's watch party shortly after the event concluded.
"Everyone's goal when they went in there was to make sure that Senator Sanders had a ceiling, and he does not have a bruise on that pretty face of his," Agnew said. "Nobody was able to land a hit. This is not spin, this is not a spin room."
The party itself, though, had some problems. The debate stopped streaming mid-way through, and remained down due to technical difficulties for about 20 minutes. - Higgins
The often messy, chaotic debate concluded after a little more than two hours. For the last question, the seven candidates listed the biggest misconception about them and said their "motto."
Some reeled off more of a campaign speech than a motto. — Pramuk
Sanders took more heat from his rivals for recent comments in which he praised a literacy program implemented by Fidel Castro's communist Cuban regime in the 1960s. He said "it's unfair to simply say everything" was bad in the dictatorship.
After he was asked about the remarks Tuesday, Sanders said "I have opposed authoritarianism all over the world." He also contended that "what I said is what Barack Obama said on Cuba," pointing to the former president saying aspects of Cuba had improved ahead of efforts to normalize U.S. relations with the country.
Former Vice President Joe Biden, who served eight years under Obama, shot back that "he did not in way suggest that there was anything positive about the Cuban government."
Former South Bend, Ind. Mayor Pete Buttigieg and Sen. Amy Klobuchar, D-Minn., also targeted Sanders over his Cuba comments. — Pramuk
As Democrats on stage criticized the Trump administration's response to the spread of coronavirus, President Donald Trump, who is currently flying back to the United States, defended his response on Twitter.
The spread of coronavirus outside of China, and warnings this week from CDC experts sent markets tanking on Monday and Tuesday. - Wilkie
The debate stopped playing at the Bernie Sanders campaign watch party in Charleston around 9:10 in the middle of an explanation from Sen. Amy Klobuchar about how she would legalize marijuana. Klobuchar said she supported legalization, but only once there was funding for treatment, prompting some confused expressions from the crowd.
"I just want to remind everyone that Senator Sanders wants to provide free broadband internet to the entire country," said Phillip Agnew, a surrogate who took the mic told the audience amid the snafu.
The surrogate added that many of the people the campaign was trying to win over were not on Twitter, so if they were tempted to send off an angry tweet during the debate, they were instead to contact people via the campaign's "Bern" app.
UPDATE: The program resumed at about 9:30. - Higgins
Mike Bloomberg deftly segued from a question about New York's trans fat ban to attacking President Donald Trump over his administration's response to coronavirus.
"If you have good public health then you can do things. You read about the [coronavirus] and what's really happening here is the president fired the pandemic specialist in this country two years ago, so there's nobody here to figure out what the hell we should be doing," Bloomberg said. "He's defunded Centers for Disease Control, so we don't have the organization we need. This is a very serious thing. As you see, the stock market is falling apart and people are very worried and they should be. This is a very serious thing and we don't have anybody to respond."
In 2018, Trump fired the majority of the White House global health emergency team. The spread of coronavirus outside of China, and warnings this week from CDC experts, sent markets tanking on Monday and Tuesday. - Wilkie
We're about an hour into this approximately two-hour debate, and the proceedings have been as feisty as expected. Bloomberg has been sharper and more engaged than he was the last time. Warren started to try to draw distinctions between herself and fellow progressive Sanders, but eventually turned her fire on Bloomberg, again. Klobuchar didn't get much time to speak at first, but she continued to scrap by pushing her bonafides in the Midwest. Sanders took a lot of heat, but stuck to his usual script bashing billionaires and wealth inequality. Buttigieg had some clever lines but was overshadowed by the more aggressive exchanges. Biden brought some fire tonight, particularly in taking on Steyer, but he also complained a lot about his rivals not following the rules. - Calia
As Mike Bloomberg keeps taking a beating on the Democratic debate stage for alleged harassment and non-disclosure agreements at Bloomberg LP, the company he founded is ramping up its sexual harassment training.
In a memo sent to employees on Tuesday afternoon, ahead of Bloomberg's second debate appearance, the company underlined its "zero tolerance" policy for harassment, while announcing a mandatory program to prevent harassment. Read the full story here. - Lauren Hirsch
Sen. Elizabeth Warren attacked Michael Bloomberg over an accusation from a former employee who claimed Bloomberg quipped "kill it" when she was discussing being pregnant.
Bloomberg flatly denied ever saying any such thing. "I'm sorry if she heard what she thought she heard," he said.
Bloomberg also grew testy over Warren's continued pressure on him to release all former Bloomberg LP employees who alleged misconduct at the company from their non-disclosure agreements. He argued that he had already released the three women who claimed that he personally said offensive things in the workplace.
Bloomberg said he was "probably wrong to make the jokes -- I don't remember what they were ... If it bothered them, I was wrong, and I apologize for that. But we went back 40 years, and we could only find three cases where women said they were uncomfortable. Nobody accused me of doing anything other than making a comment or two." - Wilkie
Former Vice President Joe Biden predicted a win in South Carolina on Saturday when he was pressed by the moderators on his sinking poll numbers in the state. Biden's lead over Sen. Bernie Sanders has been slipping in South Carolina, where the former vice president has been relying on support among black voters.
If Sanders bests Biden, it will be the Vermont senator's fourth straight popular vote victory. Coming just days before Super Tuesday, that could give him a boost toward an insurmountable delegate lead. - Higgins
Sen. Elizabeth Warren took direct aim at Sen. Bernie Sanders' reputation for being more focused on grand ideas than on actionable legislation.
"Bernie and I both wanted to help rein in Wall Street, and in 2008 we both got our chance. But I dug in, I fought the big banks, I built the coalitions and I won," Warren said.
"Bernie and I both want to see universal health care. But Bernie's plan doesn't explain how we're going to get there … I dug in, I did the work, and then Bernie's team trashed me for it. We need a president who's actually going to dig in and do the hard work and actually get it done."
Since his early days in Congress, Sanders has tended to prefer taking high-profile, far left positions than actually getting into the messy work of legislating and compromising. As a result, Sanders' relatively thin record of accomplishments in the House and Senate could be a legitimate Achilles heel later in the year. - Christina Wilkie
Former New York Mayor Mike Bloomberg ratcheted up his criticism of Sen. Bernie Sanders before the debate. It took no more than five seconds for the Vermont senator to target the businessman as a symptom of the greed of American billionaires.
Asked how he would beat President Donald Trump despite a strong economy and the lowest unemployment rate in decades, Sanders responded that "the economy is doing really great for people like Mr. Bloomberg and other billionaires." He highlighted sluggish wage growth, the number of Americans without health insurance and record student debt.
Bloomberg took a shot at Sanders' ability to deny Trump a second term. He argued that Russia reportedly tried to boost Sanders because Moscow wants the incumbent to stay in office. "Vladimir Putin thinks that Donald Trump should be president of the United States and that's why Russia is helping you get elected so you'll lose to him," he said. Sanders shook his head, saying, "Oh, My. Bloomberg."
Sanders then pointed to Bloomberg's past praise of Chinese President Xi Jinping, who has run an authoritarian regime. He said Russia wanted to sow division in the U.S. "Hey Mr. Putin, if I'm president of the United States, trust me, you're not going to interfere in any more American elections," the senator said. - Pramuk
The debate started more than 10 minutes ago, and we've heard from every candidate except for Amy Klobuchar. - Calia
A woman sitting near the front of the Bernie Sanders campaign watch party flipped Bloomberg the middle finger when he responded. Other supporters booed and jeered. - Higgins
Candidates will have one minute and 15 seconds to answer; 45 seconds for followups. - Calia
The candidates have started to take the stage. The lineup as seen on your TV/computer/phone screen, left to right: Bloomberg, Buttigieg, Warren, Sanders, Biden, Klobuchar and Steyer. - Mike Calia
The event is being hosted in a fancy food court with Filipino, Mexican, deli and burger options.
On tap: Thematic brews from local brewster 13 Stripes Brewery with names like "Not My King Lager" and "Oppose The Tyrant IPA."
Nina Turner, the national co-chair of the campaign, arrived to fire up supporters ahead of the debate.
"I believe just like Iowa, you are going to come through. Just like New Hampshire, you are going to come through. Just like Nevada, you are going to come through," Turner told the crowd. - Higgins
As the U.S. aims to contain the spreading coronavirus outbreak, Democratic White House hopefuls started to criticize the Trump administration's response to the outbreak Tuesday. It remains to be seen if they use the debate platform to pick apart the president's strategy.
Trump, a close observer of U.S. stock markets, was surely watching a two-day rout that saw the Dow Jones industrial average and S&P 500 plunge more than 6%.
Sen. Elizabeth Warren, D-Mass., said "the Trump administration is absolutely bungling the response to coronavirus, putting our public health and economy at risk." She called for more funding for public health and international aid programs, criticizing Trump's proposed cuts to U.S. health programs.
Meanwhile, former Vice President Joe Biden called for "strong American leadership and disciplined diplomacy." He contended Trump is "incapable of that" and "the worst possible person to lead our country through a global health emergency. - Jacob Pramuk
Despite the increased focus on Sanders, it's likely Bloomberg will continue to catch heat for his past remarks about minorities, transgender people, people who died from drug overdoses and other groups. In recent weeks, as he has risen in the polls, various recordings of Bloomberg making such remarks have resurfaced. Some of his comments came as recently as last year. Read our story. - Yelena Dzhanova
Democratic presidential contenders are facing what could be their last chance to halt an ascendant Sen. Bernie Sanders during the presidential debate in South Carolina on Tuesday. Indeed, Sanders is likely to face scrutiny from a united front of Democrats.
The event in Charleston, hosted by CBS News, is likely to be a rowdy affair. The debate will kick off at 8 p.m. ET and is expected to last just over two hours. It comes four days before Saturday's South Carolina primary, the last nominating contest next week's crucial Super Tuesday contests. Read our preview here. - Tucker Higgins
The debate, the 10th of the cycle, kicks off at 8 p.m. on CBS from Charleston, South Carolina. Seven candidates will be on stage tonight. They are:
Former Vice President Joe Biden
Former New York Mayor Mike Bloomberg
Former South Bend Mayor Pete Buttigieg
Sen. Amy Klobuchar of Minnesota
Sen. Bernie Sanders of Vermont
Hedge fund founder Tom Steyer
Sen. Elizabeth Warren of Massachusetts