CHICAGO, Aug 23, 2024 (BSS/AFP) - As red, white and blue balloons streamed onto a Chicago stage and people danced in the aisles, Kamala Harris waved to supporters and basked in the crowd's adulation after the speech of her political life.

As she accepted her party's nomination in the US presidential race on Thursday, nearly every sentence Harris uttered was greeted with raucous cheers, her voice reverberating around the packed auditorium.

Thirteen of those words, delivered early in the speech, electrified the house: "I accept your nomination to be president of the United States of America."

The Democratic Party has leaned hard on saying the convention was meant to be about bringing the "joy," and attendees seemed to respond to the call.

"I'm so elated, I'm so proud to be part of this moment. I'm 57 years old and as a Caribbean-American, I am proud of her," said attendee Wynnie Testamark as she clutched a US flag moments after hearing Harris accept her party's highest honor.

"She's been prepared for such a moment as this, we need a moment like this."

Expectations were high, with party members rewarded with a rendition by Pink of her hit "What About Us," lighting thousands of phone torches.

In an explosive finale to a high-energy week, Harris at once concluded her unprecedentedly abrupt elevation from supportive deputy to President Joe Biden to aiming to become the country's first woman president.

The full-to-capacity crowd waved vertical "Harris" banners in their thousands in support of their nominee, who wore a dark jacket set off with a matching cravat, and a US flag lapel pin.

"It was a lot of energy tied to what she was saying," said Fred Jones, 49, an engineering manager. "She referenced her mother telling her not to let anything stop her. That resonated with me."

It was a fitting crescendo to a week of big tent politics that saw a sitting president, two former commanders-in-chief, pro-Harris Republicans, Michelle Obama and TV star Oprah Winfrey take to the stage.

Her speech, which she continued to tweak in the hours before stepping up to the podium, touched on her resume, her family, her beliefs and her patriotism.

- 'Historic' -

The stands filled hours before the allotted hour for what could be among Harris's defining moments.

It followed a string of political firsts throughout the convention including an uncensored Barack Obama mocking Republican nominee Donald Trump, a full-throated endorsement from Oprah, and the Democratic vice presidential pick Tim Walz's son weeping with emotion.

Ardent supporters wearing "Madam President" T-shirts spontaneously broke out into applause, cheering wildly before anyone had even taken to the stage.

Those unable to get seats in the standing-room-only basketball arena thronged gangways and clamored around televisions tuned to the historic moment unfolding just steps away.

The Chicks's stirring rendition of the US national anthem, "The Star-Spangled Banner," provoked cheers that were heard well outside the convention hall.

Janitors wielding mops peeked through gaps in the curtains that separated the atrium from the outside concourse while hundreds of plainclothes security officers patrolled.

Volunteers raced around the United Center with carts stuffed with miniature US flags, "USA" posters, and cardboard "Kamala" signposts.

The celebratory atmosphere and vast crowd, which caused several Harris fans to faint, will no doubt irk Trump, who just weeks ago was facing a path to the presidency through a deflated, divided Democratic Party.

"The path that led me here in recent weeks was no doubt unexpected, but I'm no stranger to unlikely journeys," Harris said after recounting her personal history.

Later in her speech, she was definitive.

"We are not going back," a battle cry echoed by the crowd as she got into her stride.

The ecstatic atmosphere lasted long after Harris had concluded her speech.

"Historic, so powerful. Just exactly what we needed to hear," said Chicago restaurateur Bill Jacobs, 63, as he and his group danced out of the auditorium to Jon Batiste's "Freedom."