Next week, Vice President Kamala Harris and her future running mate will crisscross the country together, a source familiar confirmed to ABC News.

Beginning Tuesday, the vice president and her running mate will hit all seven battleground states starting in Pennsylvania.

The source said to read too much into the fact that Philadelphia is first up, even though Pennsylvania Gov. Josh Shapiro has been out stumping for Harris and auditioning publicly for the role.

Harris and her running mate will then head to Wisconsin, Michigan, North Carolina, Georgia, Arizona and end in Nevada.

ABC News' Mary Bruce

Vice President Kamala Harris was the only candidate to qualify for the Democratic party's presidential nominating ballot, the Democratic National Committee (DNC) announced Tuesday night.

The virtual roll call to make Harris the official Democratic nominee will begin Thursday, Aug. 1, and will end on Monday, Aug. 5.

Across the country, 3,923 delegates petitioned to make Harris the Democratic nominee, according to the DNC, which noted Harris secured the support of 99% of participating delegates.

Republican Vice Presidential candidate JD Vance said it was "time to circle the wagons and load the muskets," in a forward to a book penned by Project 2025's leader, according to a report.

The New Republic obtained the forward to "Dawn's Early Light," the book written by the Heritage Foundation leader Kevin Roberts, where Vance claims "explores many of the themes I’ve focused on in my own work."

"Never before has a figure with Roberts’s depth and stature within the American Right tried to articulate a genuinely new future for conservatism. The Heritage Foundation isn’t some random outpost on Capitol Hill; it is and has been the most influential engine of ideas for Republicans from Ronald Reagan to Donald Trump," Vance wrote in the forward, according to the report published Tuesday.

Vance claims "Roberts sees a conservatism that is focused on the family," and "cultural norms and attitudes matter."

The senator ended his forward with an analogy about a garden that "needs to be recultivated."

"As Kevin Roberts writes, 'It’s fine to take a laissez-faire approach when you are in the safety of the sunshine. But when the twilight descends and you hear the wolves, you’ve got to circle the wagons and load the muskets,'" Vance wrote, according to the report. "We are now all realizing that it’s time to circle the wagons and load the muskets. In the fights that lay ahead, these ideas are an essential weapon."

-ABC News' Soo Rin Kim

Vice President Kamala Harris is set to take the stage in Atlanta Tuesday night for her largest campaign rally to date.

Among the guests will be Megan Thee Stallion and Quavo.

During her speech, the vice president will lay out how she will prioritize the strengthening of middle-class families as president, according to a Harris official.

She will say a key to this is recognizing that prices remain too high for many essentials that families rely on, and she will lay out her plans to lower costs.

She will also discuss the state of the race, reiterating that she is the underdog in this race but has real momentum and grassroots enthusiasm at her side, and she is expected to call out former President Donald Trump for refusing to honor his commitment to debate, the official said.

Following her remarks, Harris will join a national campaign organizing call to thank volunteers for their support and talk about more ways to get involved with the campaign, the official said.

-ABC News' Gabriella Abdul-Hakim, Frtiz Farrow, Isabella Murray and Will McDuffie