Tuesday's Democratic presidential debate ballooned to a dozen candidates, all of whom appeared on a single stage at Otterbein University in Westerville, Ohio.

It was the first primary showdown since House Democrats began a formal impeachment inquiry into President Donald Trump — and it could be the last stand for some of the candidates struggling to keep pace. As always, we fact checked all the contenders in real time.

See all the claims and the facts below, and download the NBC News app for full coverage.

Who gets credit for the Consumer Financial Protection Bureau?

Joe Biden and Elizabeth Warren got into it in the third hour of the debate when the former vice president took some credit for getting Warren’s brainchild — the Consumer Financial Protection Bureau — passed into law.

"I agreed with the great job she did, and I went on the floor and got you votes. I got votes for that bill. I convinced people to vote for it. So let's get those things straight too," Biden said, earning a steely and careful response from Warren that she was "deeply grateful to President Obama" for getting the agency created.

Before she ran for Senate, Warren conceived of the regulatory agency to police the financial industry in the wake of the economic downturn. It was created by the Dodd-Frank Wall Street Reform and Consumer Protection Act, which was signed into law in 2010.

Biden, who has been criticized for close ties to the banking industry during his decades in the Senate, was undoubtedly supportive of the legislation — it was a key priority of the Obama administration. But both former Sen. Chris Dodd and former Rep. Barney Frank told The New York Times they do not recall the former vice president being a key or significant player in getting Dodd-Frank passed, undercutting his claims here.

Were Andrew Yang's numbers on manufacturing job losses in 2016 swing states correct?

In his closing remarks, Andrew Yang referenced the loss of "4 million manufacturing workers here in Ohio and Michigan and Pennsylvania and Wisconsin and Iowa" as a symptom of the "fourth industrial revolution."

His figure is way off. According to data from the Bureau of Labor Statistics, those five states lost a combined 1.09 million manufacturing jobs between the peak of national manufacturing employment, 2000, through October 2016.

There’s no data on cause, but it's clear Yang's got his numbers wrong. Nationwide, the country lost 4.9 million manufacturing jobs during the same period.

Did Bernie Sanders get his numbers right on job losses due to trade deals?

Sanders, in attacking Joe Biden, said the former vice president was responsible for helping to put into effect "trade agreements like NAFTA and PNTR with China," which, Sanders said, "cost us 4 million jobs.”

Sanders made this claim during the September debate. It was true then, and it's true now— according to several reputable analyses.

As NBC News’ Carrie Dann reported in February during President Donald Trump’s State of the Union address, job losses resulting from NAFTA tend to be overstated — but one major study found that more than 850,000 jobs were displaced by the pact.

Robert E. Scott of the pro-labor Economic Policy Institute found that about 851,700 U.S. jobs were displaced by the U.S. trade deficit with Mexico between 1993 (shortly before NAFTA was implemented) and 2014. That’s a data point that was cited by Sanders during his 2016 campaign, when he frequently decried job losses due to NAFTA. (Other studies, however, have found the job losses to be far less.)

When it comes to granting PNTR (“permanent normal trade relations” status) to China, which President George W. Bush formally did in 2001 after China entered the World Trade Organization, U.S. job losses have been larger, according to studies.

The nonpartisan Congressional Research Service wrote in 2018, citing a 2014 study by the Economic Policy Institute, that “growth in the U.S. goods trade deficit with China between 2001 and 2013 eliminated or displaced 3.2 million U.S. jobs (three-fourths of which were in manufacturing).”

If you add the 851,700 figure with the 3.2 million figure, you would see a figure that approximates the 4 million figure that Sanders referred to.

Who wants to tell Cory Booker about Robert Bork?

“We need regulation and reform. And anti-trust? I mean, Robert Bork right now is laughing in his sleep,” Sen. Cory Booker said Tuesday night, referring to the prominent conservative judge and antitrust scholar.

Bork has been dead since 2012.

Were there more opioid prescriptions than people in Ohio, as Yang said?

Yang, making a point about the devastating effect of the opioid epidemic, said that at one point, "there were more opioid prescriptions in the state of Ohio than human beings in the state of Ohio."

This is true, according to government data about opioid prescription rates in 2010, when there were 102.4 opioid prescriptions per 100 persons in the state in 2010. The prescription rate has since gone down.

Joe Biden takes credit for beating the NRA. Is he right?

Joe Biden, during a discussion on firearms, made a pair of claims about his efforts to take on the NRA — and gun violence.

“I'm the only one on this stage who has taken on the NRA and beat them, and beat them twice,” Biden said. He added, “We were able to get assault weapons off the streets and not be able to be sold for 10 years. Recent studies show that mass violence went down when that occurred.”

Biden’s claim that he’s beaten the NRA twice — he has also made this claim in a TV ad — refers to the 1994 assault weapons ban and the Brady background check bill. It’s true that Biden played a leading role in the Senate in getting both measures passed and signed into law.

However, Biden has also come under scrutiny for failing to usher any bills through a divided Congress after being tasked by President Barack Obama with gun control efforts following the 2012 Sandy Hook massacre. Biden has also been criticized for his vote in favor of a 1986 bill that the NRA has called "the law that saved gun rights" in America.

As for Biden's second claim that the 1994 assault weapons ban reduced violence — there’s some evidence to support this. A 2019 study out of the Department of Surgery at New York University School of Medicine found that “mass-shooting fatalities were 70% less likely to occur during the federal ban period,” from 1994 to 2004, when it automatically expired.

Cause and effect, however, is impossible to prove, and it’s possible that other factors contributed to this decline. But the numbers themselves were low — there were 15 less deaths during the assault ban period — and other studies said the evidence was inconclusive.

Are there 5 million assault weapons on the streets, as Kamala Harris said?

"Five million assault weapons are on the streets of America today — during the course of this debate eight people will die from gun violence," Kamala Harris said.

It’s hard to know exactly how many assault-type rifles are in circulation, but there's some evidence there are far more than 5 million of those weapons on the street. Some estimates go as high as 10 to 16 million.

Meanwhile, 100 people are killed with guns per day, according to gun control advocates, a number that includes suicides. That’s roughly four an hour, and the debate is scheduled to be three, not two, hours.

Have 90 percent of Americans not had a raise in 40 years, as Tom Steyer claimed?

Tom Steyer said that “90 percent of Americans have not had a raise for 40 years.”

This is not true.

According to a study by the Congressional Budget Office, a nonpartisan federal agency, wages across all income levels, even adjusted for inflation and taxes, rose from 1979 to 2015. The top 10 percent of wage earners, however, saw a greater increase in their wages than did all others, the study showed.

Do Sanders' statistics on homelessness, the uninsured rate and student debt hold up?

Speaking out against billionaires in America, Sanders offered up data to make his point. Did he have his numbers right?

Biden suggests he didn't warn against 'demonizing' the wealthy. Is that right?

After moderator Erin Burnett said to Biden, “You have warned against demonizing rich people,” Biden rejected he'd ever said such a thing.

“Demonizing the wealthy? What I talked about was how you get things done and the way to get things done is take a look at the tax code right now," he shot back.

But Biden did warn against demonizing the wealthy — explicitly.

Biden said at a New York City fundraiser in June that “we may not want to demonize anybody who has made money,” because “rich people are just as patriotic as poor people,” according to numerous reports about the event.

Did Donald Trump ask China to investigate Biden 'in exchange' for favorable trade terms?

Former Texas Rep. Beto O'Rourke said that President Donald Trump asked China to involve itself in the 2020 election "in exchange for favorable trade terms in an upcoming trade deal."

While the president surely called on China to probe possible political rival Joe Biden's family amid ongoing trade talks — he did so on television this month — he hasn’t publicly hinged it on “favorable” trade terms. We have not seen a record of Trump's conversations with Chinese President Xi Jinping, but the president has denied asking Beijing to probe the Bidens.

Asked explicitly if he'd be "more willing to do a trade deal with the Chinese" if they investigated his political rival, the president said, "No, it has nothing to do with it. No. No. I want to do a trade deal with China, but only if it’s good for our country."

Julián Castro claims Ohio, Michigan and Pennsylvania have lost jobs. Is that true?

Early on Tuesday night, former HUD Secretary Julián Castro said that, "Ohio, Michigan and Pennsylvania, actually, in the latest jobs data, have lost jobs, not gained them."

This doesn’t appear to be true, at least when it comes to Michigan and Pennsylvania. According to the Bureau of Labor Statistics, unemployment — both the rate and the total number of persons who are unemployed — went down in Michigan from July 2019 to August 2019, the latest month for which state data is available.

In Pennsylvania, the unemployment rate remained the same from July 2019 to August 2019. The number of people who were unemployed increased from July 2019 to August 2019, but so did the number of people who were employed.

Castro is right about Ohio, however, where both the unemployment rate and the number of persons unemployed increased from July 2019 to August 2019.