Former US vice president and Democratic elder statesman Joe Biden launched his third White House bid Thursday, becoming the frontrunner in a crowded field and painting incumbent Donald Trump as a "threat" to America.
The 76-year-old is the most experienced and best recognized Democrat in the running, a veteran campaigner who has dominated early polls following months -- even years -- of planning.
In a three-and-a-half minute launch video, Biden he couldn't stand by and watch Trump "fundamentally alter the character of this nation" during a second four-year term.
Biden criticized the president's response to a deadly 2017 white supremacist rally in Charlottesville, Virginia, recalling that Trump infamously described "very fine people" on both sides of the clashes.
"And in that moment I knew the threat to this nation was unlike any I had ever seen in my lifetime," Biden said.
The Democratic stalwart, for eight years Barack Obama's deputy, added that he couldn't remain idle while Trump stood to gut America's core values and "everything that made America America."
Trump's response was swift: he insulted Biden on Twitter, his favorite forum for smacking down rivals, casting doubt on his opponent's mental capacity.
"Welcome to the race Sleepy Joe. I only hope you have the intelligence, long in doubt, to wage a successful primary campaign," Trump tweeted.
Biden, whose working-class appeal remains intact despite nearly half a century in Washington politics, is seen as a comforting, known quantity for American voters who will be vetting 20 Democrats now officially in the race.
Hours after his announcement, the gregarious Biden was in his element, pressing flesh and taking photographs with customers and employees at a Wilmington, Delaware pizza parlor, and greeting old acquaintances.
"Who's the best person to lead the country? That's what this is going to be all about and it's going to be for the voters to decide that," he told reporters.
Even before his official launch Biden led most surveys of Democratic voters. But recent controversy over his tactile style, particularly with women, could dampen his rollout.
The RealClearPolitics poll aggregate puts him as favorite with 29.3 percent support, followed by independent Senator Bernie Sanders, who votes with the Democrats, at 23 percent.
Both white men in their mid to late 70s, the pair are unlikely to be seen as the ideal shop window for a party seeking to win over young and minority voters.
Biden finds himself in a field of unprecedented diversity -- six contenders are women and three are black -- as he makes his third presidential run, following unsuccessful attempts in 1988 and 2008.
After the death of his son Beau from cancer, Biden opted out of a presidential campaign in 2016.
As he let the suspense over his plans drag out for months, the spotlight turned to younger faces including moderate South Bend, Indiana Mayor Pete Buttigieg, who at 37 is less than half Biden's age.
Top of the polls
Complicating matters, the last weeks have been clouded by accusations from multiple women who say Biden touched them inappropriately or made them feel uncomfortable with his shows of affection.
Biden, an old-school politico who acknowledges he is quick to offer hugs and shoulder rubs, has not outright apologized, but pledged to be "more mindful" about society's changing boundaries.
Obama, through a source close to his thinking, praised Biden but pointedly avoided endorsing, preferring to "let the candidates make their cases directly to the voters."
Biden concurred, saying he had discouraged his former boss from any public blessing because "whoever wins this nomination should win it on its own merits."
Several establishment Democrats did offer swift backing, including half a dozen lawmakers and a former Democratic Party boss.
Biden, who maintains a broad political network, is expected to mount a robust ground game.
But entering the race months after several rivals, he trails in a key benchmark: fundraising. He was headed Thursday to Philadelphia, reportedly to attend a high-dollar fundraiser hosted by a telecoms executive.
On Monday he travels to Pittsburgh, another city in must-win Pennsylvania, for his first major campaign event, a labor union address.
But resistance there was early dissent among progressives, including the Justice Democrats group, which criticized the party's "old guard" for failing to stop Trump at the ballot box.
"The party needs new leadership with a bold vision capable of energizing voters in the Democratic base who stayed home in 2016," the group said in a statement.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)