The 10 leading Democratic presidential contenders took to the debate stage on Wednesday in Atlanta after a momentous day of impeachment testimony in Washington. While attention going into the event was focused on South Bend, Indiana, Mayor Pete Buttigieg, who has recently surged in the first contest state of Iowa, the young Democrat emerged largely unscathed after two hours of debate, parrying critiques from Rep. Tulsi Gabbard and Sen. Amy Klobuchar about his experience. Instead, much of the ire was directed at President Donald Trump, with Sen. Bernie Sanders of Vermont calling him the "most corrupt president in the modern history of the United States of America." "If you think a woman can't beat Donald Trump — Nancy Pelosi does it every single day," Klobuchar said at one point. Despite the harsh words, former Vice President Joe Biden chided Democrats who have chanted "lock him up" at Sanders rallies and sports events, and said if he is elected he would not order Trump to be criminally investigated. The debate itself was largely cordial, punctuated by a contentious skirmish between Sen. Kamala Harris and Gabbard that echoed moments from earlier debates. And, at one point, Sen. Cory Booker expressed his shock that Biden still disagreed with legalizing marijuana because it could be a "gateway drug." "I thought you might have been high when you said it!" Booker said. Here are the top moments from the fifth Democratic debate.

Trump impeachment takes center stage

(L-R) Democratic presidential hopefuls Mayor of South Bend Pete Buttigieg, Massachusetts Senator Elizabeth Warren, Former Vice President Joe Biden and Vermont Senator Bernie Sanders participate in the fifth Democratic primary debate of the 2020 presidential campaign season co-hosted by MSNBC and The Washington Post at Tyler Perry Studios in Atlanta, Georgia on November 20, 2019. Saul Loeb | AFP | Getty Images

The fourth day of public impeachment hearings in the House ended shortly before the debate got started. The candidates used the issue to give versions of their stump speeches. Sen. Elizabeth Warren, who has been a vocal proponent of impeachment, said she will "of course" lobby her GOP colleagues to vote to remove the president if Trump is impeached. But she said the testimony earlier in the day by Ambassador Gordon Sondland, a Trump donor who lacked foreign policy experience before his diplomatic appointment, pointed to a deeper issue. "That tells us about what's happening in Washington. The corruption. How money buys its way into Washington," Warren said.

Sanders said that if Democrats are only focused on Trump, they will lose in 2020. Sanders said they must also campaign against the "rigged" economy dominated by a "handful of billionaires." "What the American people understand is that the American Congress can walk and chew bubble gum at the same time," he said. Biden said the impeaching testimony showed that Trump "doesn't want me to be the nominee." The next president, he said, will have to go to states like Georgia and North Carolina to achieve a Senate majority, and "that's what I'll do"

Harris rips Gabbard

Democratic presidential candidate Sen. Kamala Harris (D-CA) speaks during the Democratic Presidential Debate at Tyler Perry Studios November 20, 2019 in Atlanta, Georgia. Alex Wong | Getty Images

Harris continued her spat with Hawaii Rep. Gabbard, referring to her as a Democratic candidate "who during the Obama administration spent four years, full-time on Fox News criticizing Obama" and accusing her of attacking fellow Democrats on stage. "When Donald Trump was elected, not even sworn in, [she] buddied up to Steve Bannon to get a meeting with Donald Trump in the Trump Tower, fails to call a war criminal by what he is, as a war criminal, and then spends full time during the course of this campaign again criticizing the Democratic Party."

Bannon, Trump's former chief strategist, reportedly contacted Gabbard to arrange a meeting with Trump prior to his inauguration. Gabbard has also taken heat for challenging President Barack Obama for refusing to characterize the Islamic State using the words "radical Islamic terrorism." Gabbard pushed back on Harris, accusing her of "continuing to traffic in lies and smears and innuendos because she cannot challenge the substance of the argument that I'm making." She said Harris' response "only makes me guess that she will as president continue the status quo, continue the Bush-Clinton-Trump foreign policy of regime change wars, which is deeply destructive."

Warren defends her wealth tax

Democratic presidential hopefuls (L-R) Mayor of South Bend, Indiana, Pete Buttigieg, Massachusetts Senator Elizabeth Warren and Former Vice President Joe Biden participate in the fifth Democratic primary debate of the 2020 presidential campaign season co-hosted by MSNBC and The Washington Post at Tyler Perry Studios in Atlanta, Georgia on November 20, 2019. Saul Loeb | AFP | Getty Images

Warren trumpeted her plan for a wealth tax after weeks of sparring with rich Americans over the policy made national headlines. While not mocking billionaires as harshly as she has at times, the senator from Massachusetts cited her tax policy as a tool to unite a divided country. She made the case that voters across the political spectrum care about holding the wealthiest Americans accountable and lifting up the working class.

"I'm tired of freeloading billionaires," she said in promoting taxes that would help to fund social programs such as "Medicare for All" and universal child care. Warren's plan, which would tax wealth from $50 million to $1 billion at 2% and net worth above $1 billion at 6%, polls well even among Republicans and independents. But Booker criticized it Wednesday night as the wrong way to boost tax revenue.

Biden says he wouldn't order Trump probe

Democratic presidential hopeful former Vice President Joe Biden speaks during the fifth Democratic primary debate of the 2020 presidential campaign season co-hosted by MSNBC and The Washington Post at Tyler Perry Studios in Atlanta, Georgia on November 20, 2019. Saul Loeb | AFP | Getty Images

The focus of Democrats' impeachment inquiry has been on whether Trump pressured Ukraine to investigate Biden using a White House meeting and military funds as leverage. But on Wednesday, Biden said he would not order a criminal investigation into Trump if Biden succeeds in 2020. "I would not dictate who should be prosecuted or who should be exonerated. That's not the role of the president of the United States," Biden said.

Biden said he would do "whatever is determined by the attorney general." "If that was the judgment, that he violated the law and he should be in fact criminally prosecuted, then so be it, but I would not direct it," Biden said. The last president to leave office in the face of impeachment, Richard Nixon, was pardoned by his successor Gerald Ford.

Steyer challenges Biden on climate change

Democratic presidential candidate Tom Steyer speaks during the Democratic Presidential Debate at Tyler Perry Studios November 20, 2019 in Atlanta, Georgia. Alex Wong | Getty Images

Billionaire philanthropist Tom Steyer took on Biden in a dramatic exchange over the environment, calling himself "the only person on this stage who will say that climate is the No. 1 priority for me." "Vice President Biden won't say it. Senator Warren won't say it. It is a state of emergency and I would declare a state of emergency on day one," Steyer said. "I would use the emergency powers of the presidency. I know that we have to do this." Biden fired back, saying he didn't "need a lecture from my friend" and that he believes climate change "is the existential threat to humanity."

And Biden accused Steyer of hypocrisy. The former hedge fund manager, Biden said, "was introducing more coal mines and produced more coal all around the world, according to the press, than all of Great Britain produces." Steyer responded that "everybody in this room has lived in an economy based on fossil fuels." "We all have to come to the same conclusion that I came to over a decade ago. If we're waiting for Congress to pass one of the bills — and I know everybody on this stage cares about this — but Congress has never passed an important climate bill ever. This is a problem which continues to get worse."

'Black voters are pissed off'

Democratic presidential candidate Senator Cory Booker speaks during the fifth 2020 campaign debate at the Tyler Perry Studios in Atlanta, Georgia, U.S., November 20, 2019. Brendan McDermid | Reuters

Booker took perhaps the most direct shot of the night when he targeted Biden, one of the primary race's front-runners and one of its most conservative on drug policy. During a discussion in which he said "black voters are pissed off" about politicians who appeal to them only when they need votes, the New Jersey U.S. senator criticized Biden for opposing federal marijuana legalization.