Vice President Kamala Harris, a daughter of immigrants who rose through the California political and law enforcement ranks to become the first female vice president in US history, formally secured the Democratic presidential nomination on Monday.

She is the first woman of colour to feature at the top of a major party’s ticket.

More than four years after her first attempt at the presidency collapsed, Ms Harris’ coronation as her party’s standard-bearer caps a tumultuous and frenetic period for Democrats prompted by President Joe Biden’s disastrous June debate performance that shattered his own supporters’ confidence in his re-election prospects and spurred extraordinary intraparty warfare about whether he should stay in the race.

Just as soon as Mr Biden abruptly ended his candidacy, Ms Harris and her team worked rapidly to secure backing from the 1,976 party delegates needed to clinch the nomination in a formal roll call vote.

She reached that marker at warp speed, with an Associated Press survey of delegates nationwide showing she locked down the necessary commitments a mere 32 hours after Mr Biden’s announcement.

Ms Harris’ nomination became official after a five-day round of online balloting by Democratic National Convention delegates ended on Monday night. The party had long contemplated the early virtual roll call to ensure Mr Biden would appear on the ballot in every state.

It said it would next formally certify the vote before holding a celebratory roll call at the party’s convention later this month in Chicago.

An Associated Press-NORC Centre for Public Affairs Research poll conducted after Mr Biden withdrew found 46% of Americans have a favourable view of Harris, while a nearly identical share has an unfavourable view of her.

But more Democrats say they are satisfied with her candidacy compared with that of Mr Biden, energising a party that had long been resigned to the 81-year-old Mr Biden being its nominee against former president Donald Trump, a Republican they view as an existential threat.

Already Ms Harris has telegraphed that she does not plan to veer much from the themes and policies that framed Mr Biden’s candidacy, such as democracy, gun violence prevention and abortion rights.

But her delivery can be far more fiery, particularly when she invokes her prosecutorial background to lambast Mr Trump and his 34 felony convictions for falsifying business records in connection with a hush money scheme.

“Given that unique voice of a new generation, of a prosecutor and a woman when fundamental rights, especially reproductive rights, are on the line, it’s almost as if the stars have aligned for her at this moment in history,” said Democratic Senator Alex Padilla of California, who was tapped to succeed Ms Harris in the Senate when she became vice president.