Washington, 20 August 2024 (dpa/MIA) — US Democrats have gathered in Chicago for the party's national convention, with Vice President Kamala Harris set to formally accept her nomination as candidate for president in November's election later in the week.

The four-day meeting is set to crown Harris as the Democratic Party's choice to face Republican nominee Donald Trump, less than one month after 81-year-old President Joe Biden dropped his bid for a second term as his age and mental sharpness came under growing scrutiny.

Biden, who said he was ready to "pass the torch" to younger Democratic Party voices, addressed the crowd late on Monday night.

Biden spoke of his time in office, which began shortly after the January 6, 2021 attack on the US Congressional seat in Washington. That day a crowd incited by Trump, who held a rally to promote baseless claims of election fraud in his loss to Biden, violently entered the building, killing five people.

"We were in the grip of a once-in-a-century pandemic, historic joblessness, a call for racial justice, long overdue, clear and present threats to our very democracy," Biden said.

"Yet, I believed then and I believe now, that progress was and is possible. Justice is achievable, and our best days are not behind us. They're before us," he said.

"With a grateful heart, I stand before you now on this August night to report that democracy has prevailed. Democracy has delivered, and now democracy must be preserved."

Biden entered the convention to a long standing ovation, before asking the crowd a series of questions.

"Folks, let me ask you, are you ready to vote for freedom?" he asked. "Are ready to vote for democracy and for America? Let me ask you, are you ready to elect Kamala Harris and Tim Walz?" he said as the crowd screamed their affirmation.

Earlier in the evening, Harris thanked Biden for his "historic leadership" during a surprise early appearance on stage.

"Joe, thank you for your historic leadership, for your lifetime of service to our nation, and for all you'll continue to do," Harris said. "We are forever grateful to you."

Harris was already officially selected by the 4,000 party delegates to be the Democrats' presidential nominee in an online roll call earlier this month.

The convention offers Harris a further chance to present herself and her ideas to the nation after a rollercoaster month since she announced her bid to succeed Biden on the Democratic Party ticket.

The delegates will cast symbolic votes for Harris on Tuesday evening, repeating in person what they already made official in the online vote.

They are also due to vote on the party's platform for the presidential election.

Harris has successfully rallied Democrats behind her candidacy, and has seen her poll numbers rise amid a difficult period for Trump. Harris, who is of Jamaican and Indian heritage, would be the first female president in US history if she wins.

Delegates to the convention are set to hear speeches from Harris on Thursday and her pick for vice president, Walz, on Wednesday, as well as former presidents Barack Obama and Bill Clinton.