Seven leading U.S. Democratic presidential candidates squared off in a spirited debate late Thursday, with quick attacks on the newly impeached President Donald Trump as the most corrupt leader in the country's history.

All the challengers seeking the Democratic nomination to take on Trump in next year's national election said they supported the House of Representatives' adoption 24 hours before of two articles of impeachment accusing Trump of abusing the power of the presidency to benefit himself politically and obstruction of Congress.

"We need to restore the integrity of the presidency," said former Vice President Joe Biden, the consistent front-runner in national polls of Democrats for the party's nomination. Later, Biden, commenting on the sharp political division in the U.S. between Republicans and Democrats that has widened in the three years of the Trump presidency, said he refuses "to accept the premise that we can never get together again."

Sen. Bernie Sanders of Vermont, a self-described democratic socialist running second behind Biden in many polls, called Trump "a pathological liar" who has "sold out the working people of this country."

Sen. Elizabeth Warren of Massachusetts described Trump as "the most corrupt president in a century."

"The president is not king in America," Sen. Amy Klobuchar of Minnesota said. She compared Trump's actions soliciting Ukraine to investigate Biden and his son to the Watergate political corruption scandal of the 1970s that led to the resignation of President Richard Nixon as he faced certain impeachment.

South Bend, Ind., Mayor Pete Buttigieg said Trump "has made it clear he will stop at nothing to hold on to power."

The candidates, standing on a debate stage at a Los Angeles university, aimed repeated attacks at Trump as a failed president.

They only occasionally aimed their attacks at each other. But Biden and Sanders, standing next to each, sparred sharply over health care, with Sanders shouting defense of his proposal for a universal government-run health insurance program, while Biden continued to call for more measured reforms that would allow Americans to join a government plan if they wanted to.

Nominating contests

It was the sixth debate of the presidential campaign, the second from the last before Democratic Party nominating contests start in six weeks, with caucuses in the farm state of Iowa followed quickly in the weeks after by primary elections in New Hampshire and numerous other states. The seven candidates on the debate stage constituted the smallest number yet, down from at least 10 in previous encounters, as other candidates have dropped out of the race or failed to meet national Democratic Party requirements for fundraising and voter support in multiple polls.

An obvious flaw in Thursday night's debate was the dearth of African Americans or people of color on the stage. Sen. Kamala Harris of California recently dropped out of the race because of a shortage of cash, while Sen. Cory Booker of New Jersey and former Housing and Urban Development Secretary Julian Castro were unable to meet the Democratic National Committee's increasingly challenging standing in the polls.

"It's both an honor and disappointment to be the lone candidate of color on the stage," said Andrew Yang, an Asian American entrepreneur. He said that he hoped Booker, an African American, would be back on stage for the next debate.

One wild card candidate missing, too, from Thursday night's lineup was late entrant Michael Bloomberg, the billionaire publishing magnate and former New York mayor. He is spending his own money on an expensive television advertising campaign to increase his stature in vote-rich California, the largest U.S. state, where Democrats will cast ballots in an early March nominating election.

The question of electability is a pointed concern for millions of Democratic voters. Many voters will likely base their choice of a candidate on a hunch that he or she will have the best chance to take on Trump to try to make him a single-term president and oust him from the White House, assuming he will be acquitted when his impeachment charges go to trial in the U.S. Senate.

US economy

Several of the candidates assailed Trump's oversight of the U.S. economy, even as the world's biggest economy is enjoying the country's lowest unemployment rate in five decades.

Biden said that despite robust hiring by U.S, businesses, middle-class workers are "getting crushed. We have to make sure they have an even shot."

Buttigieg said, "Folks aren't measuring" their economic well-being "by the Dow Jones" stock index, hovering near an all-time high and frequently touted by Trump as the standard for the country's economic success.

Warren said the U.S. economy "works well for the people with money," but not others.

The debate at Loyola Marymount University came after the Democrat-controlled House of Representatives approved two articles of impeachment against Trump late Wednesday for abusing the power of the presidency to benefit himself politically and obstructing a congressional investigation of his actions.

National polls of Democratic voters have shown the 77-year-old Biden, a politically left-of-center Washington fixture on his third run for the Democratic presidential nomination, consistently ahead of two other more progressive challengers who also are in their 70s, Sanders and Warren, a former Harvard law professor.

Buttigieg, Klobuchar and two others on the debate stage, wealthy environmentalist Tom Steyer and Yang, trail behind the top three, as do other candidates who did not make the debate stage after failing to meet the national Democratic Party's requirements for fundraising and a high enough standing in the polls.

Democratic field of candidates

The one-time Democratic field of more than two dozen candidates has steadily shrunk, as many candidates have dropped out of the chase for the party's nomination for lack of money and little voter support.

More Democratic candidates who did not qualify for the sixth debate continue to campaign, still hoping to make a connection with voters before voting starts in earnest early in 2020.

Biden has touted his electability chances against Trump in hypothetical matchups between the two.

Sanders and Warren also often poll ahead of Trump, as does the 37-year-old Buttigieg. But Biden usually fares better against Trump than the other three, while an occasional poll has Trump winning some of the matchups.

The polls perhaps led Trump to assume Biden would be his 2020 opponent, as he singled out the former vice president in his months-long quest to get Ukraine to investigate him and his son Hunter Biden's work for a Ukrainian natural gas company.

Trump has described the request to Ukrainian President Volodymyr Zelenskiy as "perfect," but it is at the center of the impeachment case against Trump, which is now heading to the Senate for a trial in the weeks to come -- assuming Republicans, Democrats and White House lawyers can work out rules for the proceedings.

Trump remains highly unlikely to be convicted in the Republican-majority Senate and removed from office, but he now is the third U.S. president to be impeached in the nearly two-and-a-half-century history of the United States. All of the Democratic contenders supported Trump’s impeachment. (VOA)

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