Contenders take on Joe Biden ahead of first debates

Senator Kamala Harris highlighted her experience as a prosecutor. Photo / AP

Standing before a throng of party faithful in a key early primary state, Joe Biden's leading rivals for the 2020 Democratic presidential nomination sought to undercut the former Vice-President's argument that he's the ideal Democrat to oust US President Donald Trump.

They did it without mentioning the 76-year-old front-runner at all. Biden, in turn, didn't mention them either.

California Senator Kamala Harris charged straight at Trump as she addressed hundreds of activists at the South Carolina Democratic Party Convention.

"We need somebody on our stage when it comes for that general election, who knows how to recognise a rap sheet when they see it and prosecute the case," Harris said, playing off her experience as a state and local prosecutor as she shredded Trump on a litany of policy fronts.

Then, in a seeming reference to Biden, the 54-year-old senator added that South Carolina voters mustn't "turn back the clock" but instead, "Let's start the next chapter. Let's turn the page."

It was a demonstration that Biden, who's drawn fire in recent weeks for his reversal on opposing taxpayer funding of abortion and his recollections of working with long-dead segregationist senators, won't become the Democratic nominee without an intense fight, no matter his front-runner's strategy.

The event was a last public tune-up ahead of this week's inaugural 2020 debates in Miami.

Massachusetts Senator Elizabeth Warren pitched her progressive policies as an agenda with wide reach. "People across this nation understand it is time for big, structural change in America. The time for small ideas is over," Warren said, adding the approach can draw in Democrats and Republicans.

Vermont Senator Bernie Sanders said that his agenda can win. "We defeat Trump by running a campaign of energy and enthusiasm that substantially grows voter turnout ... in a way we have never seen."

Biden had the luxury of the last word, using his draw as the last of 20 candidates at the rostrum to deliver a rapid-fire litany of policy proposals.

South Carolina boasts the largest electorate of the four early nominating states, and its mix of black voters and moderate whites gives candidates a proving ground ahead of a slate of similar Southern states with hundreds of delegates at stake.

Biden has shown particular strength in South Carolina, where he has deep relationships from previous presidential runs, friendships with two of state's former senators and his eight years as President Barack Obama's deputy.

The South Carolina crowd roared when Biden mentioned his old boss and compared his demeanour to Trump's. "Our children are watching, they're watching, and it matters what presidents say and do," Biden said. "Barack Obama they watched, and they emulated. They wanted to be like him."

- AP