Some of the 10 Democratic presidential candidates meeting in their third debate took shots at front-runner Joe Biden, while others called for unity during a night dominated by questions around race, guns and healthcare.

An anticipated fiery matchup between Biden, the moderate former vice president, and Elizabeth Warren, a liberal senator who has gained the No. 2 spot in recent opinion polls, did not quite materialize.

U.S. Senator Bernie Sanders, running a close third, sounded hoarse as he expounded on his favorite progressive topics, including healthcare, political corruption and income inequality.

Their lower-polling rivals vied to make a mark in the race to challenge incumbent Republican President Donald Trump in the November 2020 election, while another 10 Democratic candidates who did not qualify for the debate sat out this round.

Here is a look at how each of the top 10 candidates did in the Houston debate:

Pictured: Democratic U.S. presidential candidates Senator Amy Klobuchar, Senator Cory Booker, South Bend Mayor Pete Buttigieg, Senator Bernie Sanders, former Vice President Joe Biden, Senator Elizabeth Warren, Senator Kamala Harris, entrepreneur Andrew Yang, former Rep. Beto O'Rourke and former Housing Secretary Julian Castro pose before the start at the 2020 Democratic U.S. presidential debate in Houston, Texas, September 12, 2019. (Reporting by Ernest Scheyder, Tim Reid and Joseph Ax in Houston; James Oliphant, Ginger Gibson and Doina Chiacu in Washington Editing by Colleen Jenkins and Jonathan Oatis)
REUTERS/Jonathan Bachman 

JOE BIDEN:

The former vice president's best moments in Thursday's debate came early on, when he entered into a spirited exchange with his closest rivals, Sanders and Warren, over healthcare policy.

Biden was able to defend his plan, which would build on President Barack Obama's Affordable Care Act, while questioning the price tag of Sanders' and Warren's more sweeping Medicare for All proposals.

At one point, a clearly perturbed Sanders began lecturing Biden, an image that probably helped Biden's pragmatic persona as much as anything.

Sanders also seemed to blame Biden for consumers stricken with cancer being unable to afford treatments. That hit Biden too close to home: He lost his son Beau to brain cancer in 2015.

"I know a lot about cancer, let me tell you something," Biden snapped back. "It's personal to me."

Biden, 76, who has faced questions about his stamina and his misstatements on the trail, avoided significant gaffes on Thursday. REUTERS/Mike Blake 

BERNIE SANDERS:

The progressive U.S. senator from Vermont gave a full-throated defense of democratic socialism, sounding painfully hoarse as he explained the viability of Medicare for All and railed against corporate greed.

Since the last debate in July, Sanders has seen his friend and fellow liberal Warren inch past him in opinion polls for the No. 2 spot in the Democratic contest. Still, both senators continued to steer clear of personal attacks, instead stressing policy and ideology.

Sanders, at 78 the oldest candidate in the 2020 race, appeared slightly less robust with his voice raspier than usual.

He was forced to defend his signature Medicare for All legislation early on, with Biden criticizing it as too expensive.

"Every study done shows that Medicare for All is the most cost-effective approach to providing healthcare to every man, woman and child in this country," Sanders said, noting as he did in the last debate that he "wrote the damn bill." REUTERS/Mike Blake 

ELIZABETH WARREN:

Warren has risen to second place in most polls since the previous debate, yet she largely managed to avoid the attacks from fellow candidates that often come with moving into the front of the pack.

Instead, the U.S. senator from Massachusetts assumed one of her favorite positions: pairing up with Sanders to tag-team defending their shared advocacy of Medicare for All, a government takeover of the U.S. healthcare insurance system.

Warren defended accusations from Biden that the proposal would result in raising taxes for the middle class, arguing that working families would see their overall costs go down.

"Costs are going to go up for wealthier individuals and costs are going to go up for giant corporations," she said. "But for hardworking families across this country, costs are going to go down, and that's how it should work under Medicare for All in our healthcare system." REUTERS/Mike Blake 

KAMALA HARRIS:

The U.S. senator from California, who made waves when she attacked front-runner Biden and others in previous debates, turned her attention to a safer target this time.

Harris blamed Trump for cultivating a culture of "hate and intimidation" amid recent mass shootings in Texas and Ohio.

"Obviously he didn't pull the trigger, but he's certainly been tweeting out the ammunition," she said.

She likened the president to the titular character from the 1939 film "The Wizard of Oz." "When you pull back the curtain, it's a really small dude," Harris said.

At one point, Harris looked directly into the camera and spoke to Trump, "who we all know is watching," saying the "American people are so much better" than what he espouses.

"And now President Trump," Harris said, "you can go back to watching Fox News." REUTERS/Mike Blake 

PETE BUTTIGIEG:

The mayor of South Bend, Indiana, had several bright moments and showed his usual firm grasp of policy. But he failed to land a breakout moment that might propel him into the top tier of candidates.

Buttigieg, a fundraising juggernaut, has struggled to garner more than 5% support among Democratic voters in national polls over recent weeks.

He had one of his best moments when the debate turned to the war in Afghanistan, and he said he would require Congress to vote on whether to send troops to war. Buttigieg served seven months in Afghanistan in the Naval reserve.

"If our troops can summon the courage to go overseas, the least our members of Congress should be able to do is summon the courage and take a vote on whether they ought to be there," he said to applause. REUTERS/Jonathan Bachman 

ANDREW YANG:

The entrepreneur's campaign is centered on his plan to give every American a "freedom dividend" of $1,000 a month. On Thursday, he offered 10 Americans a taste of it.

Yang asked people watching the debate to go to his website and explain how $1,000 a month would help solve their problems. His campaign will select 10 recipients for a total of $120,000 in campaign funds.

"When you donate money to a presidential campaign, what happens?" he said. "The politician spends the money on TV ads and consultants, and you hope it works out. It's time to trust ourselves more than our politicians."

The announcement drew a hearty laugh from U.S. Senator Amy Klobuchar, who said, "That's good!" Pete Buttigieg, the mayor of South Bend, Indiana, said, "It's original, I'll give you that."

Yang also dropped one of the night's biggest laugh lines during a discussion on healthcare, saying, "Now, I am Asian, so I know a lot of doctors." REUTERS/Mike Blake 

BETO O'ROURKE:

Having found new focus in the wake of a tragedy, former U.S. Representative Beto O'Rourke forcefully challenged Trump and called for confiscation of assault rifles across the country.

O'Rourke described the mass shooting last month in his hometown of El Paso, Texas, as a "turning point for this country" and one that was fueled by what he described as unresolved, systemic racism. He again called Trump a white supremacist and said the president "poses a mortal threat to people of color all across the country."

O'Rourke largely resisted the urge to utter a vulgarity after ABC, host of the night's televised debate, warned candidates not to swear. The warning came after O'Rourke cursed in an interview on CNN earlier this month.

But O'Rourke seemed to relish the chance to bend that rule when asked by a moderator if he would support confiscation of certain types of assault rifles that have been used in mass shootings.

"Hell yes, we're going to take your AR-15, your AK-47," O'Rourke said. REUTERS/Mike Blake 

CORY BOOKER:

U.S. Senator Booker of New Jersey has been mired at roughly 2% in Democratic polls for months, a poor showing that has puzzled many analysts given what they say is his eloquence, wit and command of policy.

Those traits were on display on Thursday night as Booker repeatedly sought to strike a unifying message with his rivals on stage, drawing a positive response from the audience.

"The differences amongst us Democrats on the stage are not as great as the urgency for us to unite as a party, not just to beat Donald Trump, but to unite America in common cause and common purpose," he said in his opening statement.

Booker, who is black, has made racism a central issue of his campaign. But he stressed he wants practical solutions to combat it. "Racism exists. The question isn't who isn't a racist, it's who is and isn't doing something about racism," Booker said.

Booker, who also is bald, drew one of the biggest laughs of the night when he referred to Justin Trudeau, the Canadian prime minister with a thick head of hair.

"I'm the only person on this stage that finds Trudeau's hair very menacing, but they are not a national security threat," he said, mocking the use of national security grounds by the Trump administration to justify tariffs on Canada. REUTERS/Mike Blake 

AMY KLOBUCHAR:

The U.S. senator from Minnesota held fast to her Midwestern roots, stressing her middle-of-the-road politics and painting some rivals as too extreme to win the November 2020 general election.

This time around, however, Klobuchar had a comeback for rival Sanders' well-worn "I wrote the damn bill" quip about his Medicare for All plan.

"While Bernie wrote the bill, I read the bill," she said, drawing laughter.

She criticized his plan for eliminating private health insurance, saying 149 million Americans would lose their current health insurance. "I don't think it's a bold idea. I think it's a bad idea," she deadpanned.

Mostly, though, the three-term senator strove to underscore areas of agreement with rivals. During the harshest exchange of the night, when former housing secretary Julian Castro accused Biden of forgetting what he had just said, Klobuchar channeled legendary President Abraham Lincoln, interjecting, "A house divided cannot stand." REUTERS/Mike Blake 

JULIAN CASTRO:

The usually milder Castro went home with the attack dog trophy on Thursday night after taking a couple of pointed jabs at Biden, including questioning the front-runner's memory in an exchange that did not go over well with the Houston audience.

Castro, President Obama's housing secretary, clashed with Biden over how the former vice president described a provision in his healthcare plan.

"Are you forgetting what you said two minutes ago? Are you forgetting already what you said just two minutes ago?" Castro said, drawing a low roar of disapproval from the crowd.

The Texan later claimed, "I'm fulfilling the legacy of Barack Obama, and you're not."

"That'll be a surprise to him," Biden retorted.

The sharp exchange drew criticism from Buttigieg as typical Washington point scoring, but Castro was unapologetic.

"Yeah, that's called the Democratic primary election, Pete," he said. "That's called an election." REUTERS/Mike Blake