Chicago. Vice President Kamala Harris closes out the Democratic National Convention Thursday night when she accepts her party's historic presidential nomination and seizes one of her few remaining opportunities to appeal to an audience of millions.

Harris will lay out her vision for the country and prosecute her case against Republican Donald Trump, capping a whirlwind month that began when President Joe Biden ended his reelection bid and endorsed her to replace him atop the Democratic ticket.

Harris has three objectives for her speech, according to a campaign official who spoke on condition of anonymity to discuss sensitive speech preparations. She'll share her background rising from a middle-class family to protect others as a prosecutor, contrast her “optimistic” vision with Trump's “dark” agenda and evoke a sense of patriotism, the official said.

Harris spoke briefly to the convention on Monday, when she thanked Biden and celebrated his record as president, and again on Tuesday, when the beginning of her rally in Milwaukee was streamed into the convention hall after Democrats reaffirmed their nomination of her with a state-by-state roll call.

Among others who will speak before Harris on Thursday are Michigan Gov. Gretchen Whitmer, North Carolina Gov. Roy Cooper, civil rights leader Al Sharpton and Randi Weingarten, president of the American Federation of Teachers. The singer Pink also will perform.

Harris will be the first Black woman and the first person of South Asian descent to accept a major party's presidential nomination. She'll speak a day after Minnesota Gov. Tim Walz, her choice for running mate, thanked the packed Chicago arena for “bringing the joy” to the election.

“We’re all here tonight for one beautiful, simple, reason: We love this country,” Walz said as thousands of delegates hoisted vertical placards reading “Coach Walz” in red, white and blue.

Many Americans had never heard of Walz until Harris made him her running mate, and the speech was an opportunity to introduce himself. He leaned into his experiences as a football coach, his time in the National Guard and his recounting of his family’s fertility struggles -- all parts of his biography that Republicans have questioned in the days since Harris picked him.

While it’s unclear if the speech will attract new voters, he further charmed Democratic supporters with his background and helped to balance Harris’ coastal roots as a cultural representative of Midwestern states whose voters she needs this fall.

Gus Walz, the governor's 17-year-old son, openly wept throughout the speech, wiping his eyes with tissues while watching from the front row of the convention hall directly in front of the governor.

Through tears he mouthed, “That’s my dad.”