WASHINGTON, United States (AFP)— Kamala Harris hits the US campaign trail Tuesday after effectively clinching the Democratic presidential nomination, heading to the battleground state of Wisconsin to renew her attacks on Republican candidate Donald Trump.

The vice president took just 36 hours to secure enough delegates to be nominated, moving with lightning speed after President Joe Biden’s exit from the race triggered one of the largest election upheavals in modern US history.

Hollywood star George Clooney — one of the first high-profile Democratic activists to urge Biden to drop his reelection bid — on Tuesday joined a series of heavyweights in backing 59-year-old Harris to face Trump in November.

On her trip to Milwaukee, Harris is expected to launch another attack on convicted felon Trump as she leans into her past role as a California prosecutor and state attorney general.

“She is prepared to prosecute the case against Donald Trump,” said Wisconsin campaign spokeswoman Brianna Johnson.

The theme is set to resonate throughout Harris’s campaign, as she lashed out at Trump in similar terms in a speech to staff on Monday in which she said that, as a prosecutor she knew “Donald Trump’s type.”

Backed with the endorsement of Biden and other key party figures, US media reported that Harris had on Monday sailed past the number of delegates needed — 1,976 out of nearly 4,000.

The first female, black and South Asian vice president in US history said in a statement that she was proud and “I look forward to formally accepting the nomination soon.”

Harris should now be able secure the nomination on August 7 — nearly two weeks before the Democratic convention in Chicago. The party plans to hold an online vote of convention delegates.

She will also welcome the support of Clooney, a major fundraiser and longtime Biden booster who turned against the 81-year-old due to concerns about his age and mental fitness.

“President Biden has shown what true leadership is. He’s saving democracy once again. We’re all so excited to do whatever we can to support Vice President Harris in her historic quest,” Clooney said in a statement to CNN.

Support continued to pour in for Harris, with the United Steelworkers Union and philanthropist Melinda French Gates, the ex-wife of Microsoft co-founder Bill Gates, both endorsing her.

Biden stunned the world by dropping out of the race on Sunday, bowing to weeks of pressure after a disastrous debate performance against Trump raised concerns about his age and mental acuity.

The president was due to return to the White House later Tuesday from his Delaware beach house, having spent nearly a week there in COVID isolation, during which time he made his fateful decision.

Former president Trump — who survived an assassination attempt on July 13 that added to the sense of chaos surrounding the election — has relentlessly slammed both Harris and Biden.

Trump late Monday branded her “Lyin’ Kamala Harris” and said she had “terrible” poll numbers against a “fine and brilliant young man named DONALD J. TRUMP! Be careful what you wish for Democrats???”

But recent polls have shown Harris roughly neck and neck with the 78-year-old Trump, whose campaign has been forced into a drastic rethink now that Biden’s departure has made him the oldest nominee in US political history.