We're fact checking the second night of the Democratic debate, which includes contenders like former Vice President Joe Biden, Sen. Bernie Sanders of Vermont, Sen. Kirsten Gillibrand of New York and South Bend, Indiana Mayor Pete Buttigieg.

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See all the claims, and the facts, below.

Claim: Biden claims that under Obama, the U.S. built the biggest wind farm in the world

“In our administration, we built the largest wind farm in the world, the largest solar energy facility in the world,” Biden said Thursday.

The largest wind power site in the U.S. — the Alta Wind Energy Center in California — has an operational capacity of 1,548 megawatts with 586 turbines, according to 2017 data reported by the U.S. Energy Information Administration. It was built during the Obama administration, when Biden was vice president.

But China has a bigger wind farm. The Gansu Wind Farm — also known as the the Jiuquan Wind Power Base — has 7,000 turbines and an operational capacity of at least 6,000 megawatts, according to Forbes, and plans to expand to 20,000 megawatts by 2020 according to The New York Times.

Claim: Hickenlooper says Colorado 'created the first methane regulations in the country'

Hickenlooper said that in Colorado, "We are working with the oil and gas industry and we've created the first methane regulations in the country."

This is true.

As governor, Hickenlooper, relying on input from Environmental Defense Fund as well as three oil and gas companies that operate in the state, Noble Energy, Encana and Anadarko, brokered a deal to implement strict new methane emissions regulations as well as new rules requiring the energy industry to locate and fix leaks at their drilling sites.

Those rules — which were in fact the first of their kind in the U.S. at the time — required companies to capture 95 percent of all toxic pollutants and volatile organic compounds they emitted and also led to the repair of 73,000 methane leaks from 2015 to 2017, according to the Colorado Air Pollution Control Division.

Claim: Will tariffs cost Americans $800 a year, on average?

“Americans are going to pay on average $800 more a year because of these tariffs,” Buttigieg said on Thursday night, talking about the impact of President Donald Trump's trade policies.

This is true. After the president announced new tariffs this year, economists said they would cost the average household $831 per year.

Claim: Sanders' record on gun control

Sanders claimed Thursday that he's been a reliable supporter of gun control, and said that in 1988, "when it wasn’t popular, I ran on a platform of banning assault weapons and in fact lost that race for Congress."

Sanders did lose his 1988 congressional race, but multiple outlets have said the reason isn't so clear cut. Sanders also omits that in the 31 years since that race, he has had a voting record that many gun control advocates consider checkered.

Between 1991 and 1993, he voted at least three times against different iterations of the “Brady Bill” that required waiting periods for people buying guns. He also opposed a 1996 measure that would have funded Centers for Disease Control to conduct research on gun violence. In 2005, he voted in favor of a law — the Protection of Lawful Commerce in Arms Act — that essentially protected gun makers from lawsuits from the families of victims of gun violence. After being roundly criticized for that position during the 2016 Democratic primary, Sanders co-sponsored legislation in 2017 to repeal that law.

In recent years, he has taken a stronger stance geared toward gun control, speaking (including during his campaign launch speech) about the need to expand background checks and ban assault weapons.

Claim: Did Vermont reject 'Medicare For All' because of the taxes?

"Because of those taxes, Vermont rejected 'Medicare for All,'" Bennet said on Thursday night, part of his argument against the Vermont senator's signature proposal.

This is true, though it was not called "Medicare for All." The state's then-governor, Peter Shumlin, said he was abandoning plans for a universal, publicly-funded health care system because the taxes would be too high to make the program work, according to an Associated Press report at the time.

Claim: Did Biden work with segregationists to oppose busing?

"You worked with them to oppose busing," Harris said to Biden of segregationists in the Senate, criticizing him for recent remarks about the "reputation" of those senators.

This is true. Biden fought to stop certain kinds of school busing, a method of integration, teaming up with segregationists in this effort. He has long maintained he supported desegregation, however.

Claim: Sanders wonders why middle class workers haven't seen more money in 45 years

Sanders said, "How come today the worker in the middle of our economy is making no more money than he or she made 45 years ago?"

This is pretty much true. The cost of living has steadily increased, but the buying power of most Americans’ wages hasn’t budged in decades, according to a 2018 analysis from Pew Research Center. This study says that despite a strong labor market, "today's real average wage (that is, the wage after accounting for inflation)" has "about the same purchasing power it did 40 years ago."

In addition, last year, real wage growth — the difference between the growth in paychecks and the growth of inflation — fell to -0.2 percent, meaning that Americans were making less than they had before.

Claim: Did Biden negotiate a bipartisan deal to stave off the migrant crisis?

Biden, talking about violence in countries like El Salvador, Guatemala and Honduras that has prompted thousands of people to flee and seek asylum in the U.S., said he "got a bipartisan agreement ... to spend $740 million dollars to deal with the problem and that was to go to the root cause of why people are leaving in the first place."

He then said Trump disrupted that effort.

This is mostly true, though Biden’s numbers and timeline are slightly off.

Biden led the White House effort to send aid directly to the Northern Triangle countries, and a bipartisan Congress approved $750 million — not $740 million — in funding to stave off violence in the country. And the funding did help slow migration from these countries. The U.S. began diverting that funding in 2019, two years into — not exactly immediately — into Trump's term.

Claim: Will 'Medicare for All' ban private insurance?

Bennet, discussing his opposition to Sanders' "Medicare for All" proposal, said that it would "make illegal all insurance, except cosmetic."

"Bernie is a very honest person. He has said over and over again … that this will ban, make illegal, all insurance, except cosmetic except insurance I guess that’s for plastic surgery. Everything else is banned under Medicare for All," Bennet said.

This is true. The bill Bennet is referring to — a version of “Medicare for All” introduced and championed by Sanders — would do away with any private insurance that duplicates a covered benefit. The bill proposes covering just about everything from doctors and hospital visits to prescription drugs and rehab.

Claim: Buttigieg says most Americans favor a path to citizenship for undocumented immigrants

Buttigieg said that most Americans support a pathway to citizenship for 11 million undocumented immigrants and that there's "consensus" on the issue.

This is true, according to a plethora of recent polls.

According to a Gallup poll from February, 81 percent of Americans support a path to citizenship for undocumented immigrants.

Claim: Do other major countries spend 50 percent less per capita on health care?

“In most cases, [other major countries] are spending 50 percent per capita what we’re spending” on health care, Sanders said on Thursday night.

According to the Organization for Economic Co-operation and Development, the U.S. spends $10,209 per capita on health care — far and away more than any other countries reviewed by the OECD.

Most spend at least 50 percent less than the U.S. per capita on health care, according to the OECD data.

Claim: Hickenlooper says he oversaw drop in teen pregnancy

Hickenlooper touted a birth control program in Colorado, saying, "We reduced teen pregnancy by 54 percent."

This is true, though there's more to the story. While teen pregnancy rates did fall in Colorado after the Colorado Family Planning Initiative — a state program that provided IUDs or birth control implants at little or no cost for low-income women — was put into place, Hickenlooper would be hard-pressed to take all of the credit for it. The program was put in place in 2009 — two years before he took office.

According to data kept by the Colorado Department of Public Health and Environment, birth and abortion rates both declined by nearly 50 percent among teens aged 15 to 19 and by 20 percent among young women aged 20 to 24. The birth rate among teens aged 15-19 dropped 59 percent over 2009 to 2017, according to more recent data. Hickenlooper is correct in making this claim, but neglects to mention that the program went into effect under his predecessor, Democratic Gov. Bill Ritter, in 2009.

Claim: People in America are 'working two and three jobs' to make ends meet, Harris says

Harris and other Democrats often make the argument that the economy is not working for everyone, highlighting anecdotes of people they've met on the campaign trail who are working two and three jobs.

While there is no doubt that this is the reality for some, just 5 percent of Americans hold multiple jobs, according to the Bureau of Labor Statistics. That number has risen slightly over the last few years, though it is down from 6 percent in 1999.

Claim: Hickenlooper says he got Colorado 'near universal health care coverage'

Hickenlooper said Thursday that on his watch in Colorado, "We got near universal health care coverage."

This is pretty accurate. Using a provision in the Affordable Care Act, Hickenlooper expanded Medicaid in Colorado to such a degree that (according to his campaign website) “95 percent of Coloradans have health care coverage."

A reputable survey in the state — the Colorado Health Access Survey — from 2017(the latest data published) found that 93.5 percent of Coloradans had health insurance, an “all-time” high for the state.

Claim: Do three people in this country own more wealth than the bottom half of America?

Sanders said this, and he's right, according to a report published by a left-leaning think tank, Institute for Policy Studies, which used data from Forbes’ annual ranking of the 400 richest Americans.