DETROIT (AFP) - Democratic front runner Joe Biden went on the offensive on Wednesday (July 31) against his main 2020 election opponents but was rapidly assailed on the debate stage over key issues like healthcare, race, immigration and criminal justice.
Tensions rose rapidly between the former vice-president and Senator Kamala Harris, the most prominent African American in the field, as the two reprised their clash from a month earlier at the debut debate.
But while Mr Biden aimed aggressive attacks at Ms Harris and her healthcare plan, other rivals on stage in the second night of the two-night, 20-candidate debate sought to undercut him on a host of issues.
Mr Biden is polling far ahead of his rivals for the nod to take on President Donald Trump in 2020.
The front runner found himself in a series of sharp exchanges with the other Democrats, who attacked him on his healthcare plan, stance on climate change and his past legislative record, including his failure to take decisive action against illegal immigration.
When Mr Biden jousted with Ms Harris about her "double talk" on her own modified Medicare for All plan, Ms Harris shot back: "Vice-president Biden, you're simply inaccurate."
But Ms Harris was not done. She renewed the criticism that gave her a viral moment in the first debate by accusing Mr Biden of making light of his work with the segregationists he served with in the Senate in the 1970s.
"The vice-president has still failed to acknowledge that it was wrong to take the position that he took at that time," the lawmaker said.
The crisp attacks came after the deep fault lines in the party between centrists and the progressive wing were exposed during the first night of debates between 10 other candidates.
In one of the few moments of broad unity onstage, several candidates joined Mr Biden in condemning Mr Trump.
Senator Cory Booker called him a "demagogue", Congresswoman Tulsi Gabbard said the President "is not behaving like a patriot", and Mr Julian Castro, the only Latino in the field, branded Mr Trump an outright "racist".
But much of the night was consumed with clashes between the candidates, and Mr Biden - under pressure to come out re-energised and surefooted - was poised to counter-punch against Ms Harris after she got under his skin in the first debate.
But even as his advisers urged him to be more aggressive, the 76-year-old Mr Biden took a curious first step: disarming and dismissing perhaps his most formidable rival.
Moments before the debate began, Mr Biden greeted Ms Harris, a 54-year-old former California attorney-general, by shaking her hand and saying, "Go easy on me, kid."
The intense debate the night before exposed deep fault lines between the party's progressive wing led by candidates Bernie Sanders and Elizabeth Warren, and centrists who warned that overzealous liberal policies would turn off millions of voters across the country.
Wednesday's progressive candidates highlighted the divisions, too.
"Middle ground approaches are not enough," said Washington Governor Jay Inslee, whose singular issue is climate change and has released a trillion-dollar plan to tackle it.
"We must confront the fossil fuel industry," he added.
New York Mayor Bill de Blasio, in the race's far left lane, laid down the gauntlet demanding bold change, saying he was fully prepared to "restructure society".
"We will tax the hell out of the wealthy," he boomed.
Low-polling candidates on the stage like Mr de Blasio, Mr Inslee, Senator Kirsten Gillibrand and entrepreneur Andrew Yang are desperate for breakout moments to boost their exposure and justify staying in the race, but few were evident.
The stakes are high, with the 20 candidates likely to be winnowed by as much as half ahead of the next showdown in September.
Mr Booker, seeking his own breakout, entered into a searing exchange with Mr Biden over his criminal justice record.
"There are people right now in prison for life for drug offences because you stood up and used that tough-on-crime phoney rhetoric that got a lot of people elected, but destroyed communities like mine," Mr Booker said.
Mr Biden countered by arguing that Newark's police department was troubled when Mr Booker was mayor there and advocated a stop-and-frisk policy targeting blacks.
"This isn't about the past. This is about the present," Mr Booker shot back. "I'm happy you evolved, but you have offered no redemption to the people in prison right now."
Mr Castro also attacked Mr Biden for standing with Mr Obama amid ramped up deportations.
"It looks like one of us has learnt the lesson of the past and one of us hasn't," Mr Castro, who served as Mr Obama's housing secretary, told Mr Biden.
But Mr Biden hit back at Mr Castro's controversial proposal to decriminalise illegal border crossings: "I have guts enough to say his plan doesn't make sense."