Chart showing support for top candidates in the US Democratic presidential nomination race as of Nov 19, according to RealClearPolitics polling average.
Chart showing support for top candidates in the US Democratic presidential nomination race as of Nov 19, according to RealClearPolitics polling average. AFP / Gal ROMA

Divides between Democrats vying to challenge President Donald Trump in the 2020 election were laid bare in a combative debate Wednesday, as the campaign's rising star Pete Buttigieg acknowledged he faced challenges in attracting black voters.

Buttigieg, the contest's youngest candidate who occupies the same moderate lane as frontrunner Joe Biden, offered a unifying message as a way to bring Democrats and Republicans toward a broad political middle.

Democrats can seize a majority on issues like immigration and guns "if we can galvanize, not polarize that majority," Buttigieg told the debate in Georgia.

But after an opening phase dominated by talk of impeachment of Trump, participants in the fifth Democratic debate locked horns over the costly universal health care program supported by liberal senators Elizabeth Warren and Bernie Sanders.

"I believe that commanding people to accept that option, whether we wait three years as Senator Warren has proposed or whether you do it right out of the gate is not the right approach to unify the American people around a very, very big transformation that we now have an opportunity to deliver," Buttigieg said.

Former vice president Biden also took aim at the trillion-dollar reform, saying it would be wiser to build on existing Obamacare and provide a public option.

"The fact is that right now the vast majority of Democrats do not support Medicare for All," Biden said.

Biden is the face of the Democratic Party establishment and is the current frontrunner. He turned 77 on Wednesday and appeared to stumble over his words on several occasions, including during his opening remarks.

Buttigieg, the military veteran mayor of South Bend, Indiana, who at 37 is less than half Biden's age, sought to paint himself as a young outsider who should be elected commander-in-chief despite his slender resume.

"I get it's not traditional establishment Washington experience, but I would argue we need something very different right now," Buttigieg, mayor of a small city in Indiana, told his rivals.

The top candidates in the Democratic presidential nomination race (from left) -- Mayor Pete Buttigieg, Senator Elizabeth Warren, former vice president Joe Biden and Senator Bernie Sanders -- squared off in the party's fifth debate of the 2020 cycle
The top candidates in the Democratic presidential nomination race (from left) -- Mayor Pete Buttigieg, Senator Elizabeth Warren, former vice president Joe Biden and Senator Bernie Sanders -- squared off in the party's fifth debate of the 2020 cycle AFP / SAUL LOEB

But when pressed by Senator Kamala Harris, the only black woman in the race, about his low polling among African-American voters, Buttigieg acknowledged he had yet to convince one of the party's most important constituencies.

"I welcome the challenge of connecting with black voters in America who don't yet know me," said Buttigieg, the first major openly-gay US presidential candidate.

"While I do not have the experience of ever having been discriminated against because of the color of my skin, I do have the experience of sometimes feeling like a stranger in my own country."

Biden leads in national polling, followed by Warren and Sanders.

But Buttigieg has cracked into the top tier in the past month, and now tops the polls in Iowa which stages the first nomination contest in February.

Warren was the candidate to watch last month but her campaign has plateaued.

Democratic presidential hopefuls (L-R) Senator Cory Booker, US Representative Tulsi Gabbard, Senator Amy Klobuchar and South Bend, Indiana Mayor Pete Buttigieg were among 10 candidates in the latest Democratic debate
Democratic presidential hopefuls (L-R) Senator Cory Booker, US Representative Tulsi Gabbard, Senator Amy Klobuchar and South Bend, Indiana Mayor Pete Buttigieg were among 10 candidates in the latest Democratic debate AFP / SAUL LOEB

She has made headway by pledging to end a system that she described during the debate as working "better for... the rich and well-connected, and worse and worse for everyone else.

"I'm tired of freeloading billionaires," she said.

As the 10 qualifying candidates rumbled in their nationally televised showdown, dominating the political discourse is the high-stakes impeachment hearings into Trump's dealings with Ukraine.

Democrats accuse Trump of conditioning military aid and a White House meeting on Kiev's announcing investigations of Biden and his son Hunter, who worked with a Ukrainian energy company while his father was vice president.

But some candidates warned that obsessing over the president could sabotage Democrats' efforts.

"We cannot simply be consumed by Donald Trump," Sanders said. "Because if we are, you know what? We're going to lose the election."

With attention directed at Capitol Hill, the debate run-up has been low-key.

But candidates lept at the chance to critique Trump's foreign policy on North Korea and Saudi Arabia.

Harris landed a sharp blow, saying Trump "got punked" by North Korea's leader Kim Jong Un.

One of the most heated exchanges came when Buttigieg ridiculed long-shot candidate Tulsi Gabbard for meeting "a murderous dictator" like Syrian leader Bashar al-Assad as the mild-mannered mayor snapped back at criticism over recent comments on Mexico.

There were lighter moments too. Senator Cory Booker, known for his moral calls to action, used humor to upbraid Biden for recently saying he opposed legalizing marijuana nationally.

"I thought you might have been high when you said it," said Booker, who went on to declare that America's war on drugs has been "a war on black and brown people."

Senator Amy Klobuchar, entrepreneur Andrew Yang and investor-turned-activist Tom Steyer rounded out the contenders.

The field may soon expand to include billionaire businessman and former New York mayor Michael Bloomberg who has recently filed ballot paperwork in two states.