Washington, July 23 : Vice-President Kamala Harris on Monday kicked off her presidential campaign, saying of her Republican rival that "I know Donald Trump's type" from dealing with cheats, fraudsters and abusers of women in her previous career as a public prosecutor.

Harris also framed the contest as one between two visions. One vision, hers, "focussed on the future" and the second, Trump's, "focussed on the past".

Harris spoke forcefully and energetically during her first visit to her campaign headquarters in Wilmington, Delaware, with President Joe Biden joining in on the phone from one of his homes where he is recovering from a Covid-19 infection.

Harris has adopted Biden's campaign and staff and his administration's achievements, hoping to use the next 100 or so days to the close of polling to conduct a historic race.

Biden appealed to the staff to "embrace" Harris and work as they would for him.

Harris's speech was received with whoops of encouragement and enthusiasm with a top official acknowledging at the top the campaign had raised $81 million in just 24 hours since her elevation to the top of the ticket. Democrats are looking energised and are rallying behind the Vice-President in growing numbers shrugging off self-doubts that had seized them since Biden's shocking bad performance in the first presidential debate. The campaign said it has enrolled more than 20,000 new volunteers.

"In those roles," Harris said, recounting for the audience her career as a public prosecutor from a district court in Alameda to being the Attorney General of California, "I took on predators who abused women, fraudsters who ripped off consumers, cheats who broke the rules for their gain. So, hear me when I say I know Donald Trump's type."

The audience cheered her on with loud whoops after every few words.

"As a young prosecutor when I was in the Alameda County District Attorney's office in California, I specialised in cases involving sexual abuse," Harris said.

"Donald Trump was found liable by a jury for committing sexual abuse."