Kamala Harris often leans on a favored phrase to focus her team before beginning an important project: “What business are we trying to accomplish here?”
In deciding what to say in the most important speech of her life on Thursday, the vice president’s answer has been threefold, aides said: tell her life story, frame her contest with Donald J. Trump as one pitting the future against the past and reclaim the banner of patriotism for the Democratic ticket.
Ms. Harris has been taking her convention address so seriously that she has held rehearsals complete with teleprompters in three different time zones.
Soon after she became a presidential candidate one month ago, she told advisers that she saw this speech and any fall debates as the most pivotal moments of the abbreviated race, according to three people familiar with her thinking. But in reality, she saw this speech as crucial for even longer than that. The earliest draft of her convention remarks had first circulated back when Ms. Harris was still just a vice president seeking a second term as President Biden’s No. 2.
Now, the reworked address will represent Ms. Harris’s biggest turn on the national stage since her sudden ascent to the top of the Democratic Party as she prepares to take on Mr. Trump in an election just 75 days away.
The preparations over both her message and her delivery have been intensive. Adam Frankel, a former speechwriter for former President Barack Obama and now an adviser to Ms. Harris, is the lead writer of the address, taking input and suggestions from a wide variety of others. But the vice president herself has workshopped the speech nearly line by line, two people familiar with the preparations say.
Her rehearsals and discussion sessions have involved teleprompters this week in Chicago at the Park Hyatt hotel, at Howard University in Washington and in Arizona during her first swing-state campaign trip, when some advisers traveled to join her at a downtown Phoenix hotel.
“She understands how important it is,” said Cedric Richmond, an adviser to Ms. Harris. “I think she probably overstands how important the moment is.”
The first of the three themes of the speech, according to campaign officials with knowledge of it who were not authorized to speak publicly before the address, is to tell the story of her own life. Ms. Harris is expected to describe her own middle-class upbringing, framing it as allowing her to better understand the needs and struggles of the middle class today. And she is expected to tell voters about her career before the vice presidency: her early work as a prosecutor who rose to become the attorney general of California.
