Live updates: Harris and Walz take the stage in 1st joint campaign rally

Newly-selected VP pick Tim Walz has posted his first advertisement. The spot briefly describes his background while running through a list of accomplishments from his time as Minnesota governor.

The ad is voiced over by Walz himself, and displays photos of him as a child, in the Army National Guard, as a schoolteacher and as a governor.

"Growing up, I learned to be generous toward my neighbors, compromise without compromising my values, and to work for the common good. @KamalaHarris and I both believe in that common good - in that fundamental promise of America. We're ready to fight for it. And like she says: when we fight, we win," Walz wrote in a post on X, accompanying the video.

When asked if he's willing to debate Gov. Tim Walz, Sen. JD Vance said he wants to but is going to wait until Walz is the official vice presidential nominee.

"I absolutely want to debate Tim Walz, but I want to debate him, actually, after he's actually officially the nominee, and I did call him and congratulate him and offered him my best wishes. I think that's the polite thing to do," he said.

West Virginia Sen. Joe Manchin wrote in a statement on X that "I can think of no one better than Governor Walz to help bring our country closer together and bring balance back to the Democratic Party."

"My friend Governor Tim Walz will bring normality back to the most chaotic political environment that most of us have ever seen," he said, in part, also calling him "the real deal."

Minnesota Sen. Amy Klobuchar spoke to ABC News Live about her reaction Gov. Tim Walz being selected as Vice President Kamala Harris' running mate.

The senator called Walz a "close friend," and said Harris chose the governor for several major reasons.

Minnesota Sen. Amy Klobuchar spoke to ABC News Live about her reaction Gov. Tim Walz being selected as Vice President Kamala Harris' running mate.

"She had someone in Tim Walz that one, she trusted, [and] two, she saw as someone that is going to bring something else to this ticket in a big way," Klobuchar said.