The crowd at the United Center got on their feet when former Secretary of State Hillary Clinton took the stage where she supported Harris and applauded Biden.

"There is a lot of energy in this room -- just like there is a lot of energy in this country," she said.

Clinton saluted Biden, calling him "democracy's champion," and praising his years of service.

"He brought dignity, decency and competence back to the White House," she said.

Clinton talked about the long history of bringing women's voices heard and the number of glass ceilings that were broken, including her 2016 presidential nomination.

"I wish my mother and Kamala's mother could see us. They would say, 'Keep going,'" she said.

The crowd chanted "Keep going," in response.

She also took a jab a Trump, joking that he fell asleep during his own trial. The crowd shouted "lock him up," turning the tables on the chant used at Trump rallies against Clinton.

Clinton smiled as the crowd chanted.

Clinton said that as president, Harris would be a fighter for all Americans, and cares about America.

"I know what it takes, and I can tell you, as commander in chief, Kamala won't disrespect our military and our veterans," she said.

Clinton told the crowd that they are still needed to fight for every vote and not just depend on the poll numbers.

"When a barrier falls for one of us, it falls and clears the way for all of us. So for the next 78 days, we need to work harder than we ever have," she said.

The crowd erupted in chants of "lock him up" during Hillary Clinton's speech after she highlighted the history that was made with his 34 felony convictions in New York.

After trying to continue her speech at the start of the chants, Clinton smiled and nodded before carrying on with her remarks.

Trump famously encouraged "lock her up" chants during his 2016 run against Clinton, accusing her of criminal wrongdoing though she never faced a single charge.

Actor Tony Goldwyn kickstarted a segment about Harris' story, which he said began in a middle-class, tight-knit neighborhood in the East Bay of California.

"These are the experiences that made her the leader she is today," Goldwyn said.

A video then aired featuring testimonials of a young Harris from her sister Maya Harris, her friend Stacey Johnson-Batiste and her mother's friend Lenore Pomerance.

Johnson-Batiste recalled a young Kamala Harris defending her on the playground.

"This one particular day, we had made some clay art and this one boy in our class had taken mine for whatever reason and threw it on the ground and it shattered. So Kamala, being very protective, just jumped in front of me and stood up to him. To me, that shows the kind of person that she has always been, to stand up to the bully and to stand up for the underdog and to stand up for what is right," Johnson-Batiste said.

New York Rep. Alexandria Ocasio-Cortez riled up the crowd when she went after Trump while urging voters to make history in electing Harris as president.

"Chicago, we have to help her win, because we know that Donald Trump would sell this country for a dollar if it meant lining his own pockets and greasing the palms of his Wall Street friends," she said.

"And I, for one, am tired of hearing about how a two-bit union buster thinks of himself as more of a patriot than the woman who fights every single day to lift working people out from under the boots of greed trampling on our way of life," she said to rapturous applause.

"The truth is, Don, you cannot love this country if you only fight for the wealthy and big business. To love this country is to fight for its people," she continued.

Ocasio-Cortez briefly mentioned the Israel-Hamas war, saying Harris is "working tirelessly" to secure a cease-fire in Gaza and bring hostages home.