Election 2024 updates: Trump campaign claims it was hacked by 'foreign sources'

Vice President Kamala Harris' choice for her running mate is the "most important" decision she has to make as her campaign gets started, former House Speaker Nancy Pelosi said.

All of her choices for a running mate appear to be good, Pelosi added.

"It's a difficult decision because they are all so great," she told ABC News' George Stephanopoulos on "Good Morning America" on Monday. "It is the most important decision for her to make. Not just about who can help win, but who can help serve and lead and whose confidence she trusts.

-ABC News' Kevin Shalvey

Vice President Kamala Harris and her running mate, who is yet to be named, will go on tour, hitting seven battleground states in five days, the Harris campaign said Monday.

The tour will be an effort to "introduce the new Democratic ticket" and "speak directly with voters in their communities and cement the contrast between our ticket and Trump’s,” campaign said.

The tour, which kicks off Tuesday in Philadelphia, Pennsylvania, will feature rallies in cities and stops at college campuses, including HBCUs, union halls, family-owned restaurants and their field offices, the campaign said.

The tour will continue through Eau Claire, Wisconsin; Detroit, Michigan; Durham, North Carolina; Savannah, Georgia; Phoenix, Arizona; and Las Vegas, Nevada, the campaign said.

-ABC News’ Fritz Farrow, Gabriella Abdul-Hakim, Isabella Murray and Will McDuffie

Vice President Harris is meeting with top running mate candidates Sunday at her residence at the Naval Observatory in Washington, D.C., according to a source familiar with the matter.

Harris is meeting with at least three leading contenders -- Arizona Sen. Mark Kelly, Minnesota Gov. Tim Walz and Pennsylvania Gov. Josh Shapiro, according to the source.

The meetings were earlier reported by The New York Times.

-ABC News' Selina Wang

In a Fox News interview Sunday, Sen. JD Vance responded to criticism of him being picked as former President Donald Trump’s running mate, saying he takes it as a "badge of honor."

"All I can do is go out there and prosecute the case against Kamala Harris to remind people that things were more prosperous and more peaceful when Donald Trump was president," Vance said. "Look, I recognize there are a lot of folks even in the GOP establishment and certainly on the far left who don't like the fact that Donald Trump picked me, I actually take their criticism as a badge of honor."

Vance also hit back at Democrats who’ve called him "weird," calling it "a lot of projection."

"They can call me whatever they want to. The middle school taunts don't bother me," he said. "What offends me is what Kamala Harris has done to this country over three and a half years."

-ABC News' Lalee Ibssa, Soo Rin Kim, Kelsey Walsh and Hannah Demissie