Chicago (AFP) - Kamala Harris accepted the Democratic presidential nomination in Chicago on Thursday in front of a rapturous crowd, pledging a “new way forward” if she beats Republican Donald Trump in November’s blockbuster election.

“On behalf of everyone whose story could only be written in the greatest nation on earth, I accept your nomination to be president of the United States of America,” the 59-year-old said to huge cheers.

“I will be a president who unites us around our highest aspirations,” she said.

A sea of waving Stars and Stripes flags and chants of “USA” filled the arena as jubilant Democrats anointed Harris as their standard-bearer.

Harris pledged to be a “president for all Americans” as she reaches out to undecided American voters after one of the most stunning upheavals in US political history.

With the November election, Americans have a “fleeting opportunity to move past the bitterness, cynicism and divisive battles of the past – a chance to chart a new way forward,” she promised.

She laid out her personal story as a child of a single working mother, and her career as a prosecutor, saying she has the background and experience to serve the country in contrast to Trump who she said only works for himself and “his billionaire friends.”

The convention became a giant party to celebrate Harris’s astonishing ascent.

Country act The Chicks sang a version of “The Star-Spangled Banner” while pop star Pink also performed as the Democrats rolled out a list of celebrity backers.

- ‘President for all Americans’ -

The Democrats are riding on a huge wave of energy and enthusiasm after Harris took on the mantle from President Joe Biden amid concerns over his health at 81 years old.

The first Black woman nominee for a major party, Harris has wiped out former president Trump’s lead in the polls, drawn enormous crowds and raised record funds.

Now her challenge is to introduce herself to a country is still getting used to the new Democratic candidate.

“I know there are people of various political views watching tonight. And I want you to know: I promise to be a president for all Americans,” Harris said.

She talked about being raised by a working, single mother, insisting she understood the challenges facing families hit by inflation.

Harris also recounted her prosecutorial career fighting for victims of sexual abuse and gun crime, highlighting the fact that in Trump she now faces the first convicted felon ever to seek the White House.

The torch having well and truly been passed, Biden gave a farewell speech on the first day of the convention and said he had called Harris to wish her luck.

“I am proud to watch my partner Kamala Harris accept our nomination for president. She will be an outstanding president because she is fighting for our future,” Biden, who is on holiday in California, said on X.

- Tempered hopes -

Yet Democrats will also be trying to temper their hopes, knowing that Harris faces a tough sprint to a nail-biting election on November 5, which as in 2020 may be decided by a handful of votes in key states.

From Barack and Michelle Obama to Bill Clinton, senior figures have warned all week that Harris has a brutal fight on her hands to beat Trump.

Trump, 78, believed he was cruising to a stunning return to power against Biden. Instead he has been unsettled by the sudden Democratic switch to a much younger opponent – and one looking to make history as the first female president.

The Republican is increasingly resorting to personal insults and race-baiting.

Speaking near the Mexican border barrier built during his presidency in the battleground state of Arizona, Trump focused Thursday on immigration, which Republicans believe is a major weakness for Harris.

Recounting stories of people he said were killed by migrants who had come across the border illegally, he said: “As Kamala gives her convention speech tonight, she will not mention the victims. She won’t even mention their names.”