WASHINGTON, DC, USA (AP) — Declaring the “soul of this nation” at stake, former Vice-President Joe Biden pushed into the crowded 2020 presidential contest yesterday and quickly sparked a fierce debate over the direction of the modern-day Democratic Party.

Ignoring the political noise in his own party, Biden aimed directly at Donald Trump in an announcement by video, seizing on the Republican president’s response to the deadly clash between white supremacists and counter protesters in Charlottesville, Virginia, two years ago. That was the spur for him to launch a third presidential bid, Biden said, noting Trump’s comments that there were some “very fine people” on both sides of the violent encounter, which left one woman dead.

“We are in the battle for the soul of this nation,” Biden declared. “If we give Donald Trump eight years in the White House, he will forever and fundamentally alter the character of this nation — who we are. And I cannot stand by and watch that happen.”

Yet Biden will get a chance to take on Trump only if he survives a Democratic field that now spans at least 20 contenders. And his party’s more liberal wing was far from welcoming in the hours immediately after he declared his candidacy. Justice Democrats, a group created from the remnants of Bernie Sanders’ failed 2016 campaign, came out against Biden on Thursday and spent much of the day assailing him on social media.

As an older white man with often-centrist views, Biden must now prove he’s not out of step with Democrats trying to push the party to the left.

Biden has highlighted his role in authoring the Violence Against Women Act nearly three decades ago, legislation that is credited with reducing domestic violence nationwide.

Still, the 76-year-old Scranton-Pennsylvania native’s political liabilities are many.

He would be the oldest person ever elected president — Trump was 70 in 2016 — even as his party embraces a new generation of diversity. He’s also yet to outline his positions on issues defining the 2020 Democratic primary, most notably “Medicare for All,” the universal health care plan authored by Sanders that has been embraced in one form or another by virtually the entire Democratic field.

Biden is betting that his working class appeal and ties to Barack Obama’s presidency will help him win over sceptics. He quickly racked up endorsements yesterday morning, becoming the first Democrat running for president with the backing of more than one US senator.

Rep Cedric Richmond, D-La, who previously served as chairman of the Congressional Black Caucus, said he had urged the former vice-president to run and highlighted Biden’s potential electability when asked to assess African Americans’ feelings.

“Black voters are saying the same thing that white Democrats are saying: We can’t afford to lose. That is a big message. That’s a big motivator,” Richmond said.

Trump was quick to pounce on Biden, who he has nicknamed, “Sleepy Joe”.

“I only hope you have the intelligence, long in doubt, to wage a successful primary campaign,” Trump said. “It will be nasty; you will be dealing with people who truly have some very sick and demented ideas. But if you make it, I will see you at the starting gate.”

Privately, Trump allies have warned that Biden might be the biggest re-election threat given the former vice-president’s potential appeal among the white working class in the Midwest, the region that gave Trump a path to the presidency.