WASHINGTON, United States (AFP)— US Vice President Kamala Harris launched her election campaign Monday with a blistering personal attack on Donald Trump and vowed to win in November despite the “rollercoaster” of President Joe Biden’s shock exit.

As she closed in on the Democratic party’s nomination with the support of a slew of heavyweights and massive voter donations, Harris lashed out at Trump in her first speech to campaign workers since Biden’s announcement Sunday.

Biden, 81, meanwhile made his first public remarks for nearly a week as he recovers from a bout of COVID.

He called in to the campaign meeting to say that dropping out — after mounting party and voter concerns over his health and mental acuity — had been the “right thing to do” and he praised Harris as “the best.”

“We are going to win in November,” a smiling Harris told campaign workers in her fiery speech at campaign headquarters in Wilmington, Delaware.

She said she had gone to the Wilmington office to address them personally after the “rollercoaster” of the last few days.

Turning her fire on Trump, Harris referred to her past role as California’s chief prosecutor, saying she “took on perpetrators of all kinds.”

“Predators who abused women. Fraudsters who ripped off consumers. Cheaters who broke the rules for their own gain. So hear me when I say I know Donald Trump’s type,” she said to applause.

Harris also pledged to focus on the politically explosive issue of abortion, after Trump praised the Supreme Court’s 2022 decision to overturn the long-held federal right to the procedure.

Biden dropped out on Sunday and endorsed Harris after three weeks of intensifying pressure, triggered by a disastrous debate performance against Trump.

Aiming to become the first woman president in US history, the 59-year-old Harris won the backing of a seemingly unassailable number of Democrats.

Notably among them was powerful former US House speaker Nancy Pelosi, who said she endorsed Harris “with immense pride and limitless optimism.”

The major AFL-CIO union federation also gave its formal endorsement on Monday.

Donors have rallied behind Harris, pouring a record $81 million into her campaign in the 24 hours after Biden stood aside.

The campaign claimed the haul was the largest one-day sum in presidential history — and that, among the 888,000 grassroots donors, some 60 per cent were making their first 2024 contribution.

In his comments, Biden pledged to keep working on key topics, including ending the war in Gaza.

Addressing Harris, he added: “I’m watching you kid. I love you.”