Twenty-two Democratic governors are lauding the fact that their colleague, Minnesota Gov. Tim Walz, has joined the 2024 Democratic ticket.

In a statement released on Wednesday, they stressed as a group of leaders -- which includes some they said were "elected in very challenging races in battleground and red states" -- that they were "thrilled" with Harris' selection.

The joint statement was notably signed by Pennsylvania Gov. Josh Shapiro, Kentucky Gov. Andy Beshear and Illinois Gov. JB Pritzker, who themselves were on the shortlist of potential Harris vice presidential picks. All three had submitted materials to the Democratic nominee's vetting team, though only Shapiro had traveled to Washington, D.C., on Sunday for an in-person interview with Harris.

"As America’s Democratic governors, we represent a broad and diverse set of 23 states that make up more than half the U.S. population. Many of us were elected in very challenging races in battleground and red states. We make tough decisions as state executives every day, and know what it takes to win. We couldn't be more thrilled that Vice President Kamala Harris has selected Governor Tim Walz as her running mate, and will do everything in our power to ensure their success this November," the statement, first shared with ABC News, reads.

"Overall, there’s no doubt the Harris-Walz ticket is the perfect one-two punch to knock out the GOP's dangerous agenda and failure to deliver for the American people," the statement continues.

Other governors who signed on to the letter include California's Gavin Newsom, Michigan's Gretchen Whitmer, Colorado's Jared Polis, Maryland's Wes Moore and North Carolina's Roy Cooper.

GOP vice presidential nominee Sen. JD Vance delivered remarks following a briefing with the Shelby Township, Michigan, Police Department on Wednesday, where he went after Vice President Kamala Harris on her "policy choices."

Vance's remarks at the event focused on supporting law enforcement and combating undocumented immigration.

"We've got to throw Kamala Harris out of office, not give her a promotion, and that's what our law enforcement needs," he said.

When asked by reporters about how a Trump administration would actually deport undocumented immigrants (Trump has repeatedly vowed to deport millions of migrants), Vance gave no real plan on how that would happen but stated: "We are going to deport people now."

Vance also took aim at his Democratic VP opponent, Minnesota Gov. Tim Walz, a retired National Guardsman, questioning his military service while providing no facts to back up his claim. Vance also called out Walz for his comment during Tuesday's rally in Philadelphia, where the governor called out the senator's Ivy League education and support from tech billionaires.

"And if he wants to criticize me for getting an Ivy League education, I'm proud of the fact that my mama supported me, that I was able to make something of myself," Vance said.

Vance was again asked his thoughts about Trump falsely questioning Harris' racial identity. Vance said he viewed Trump's attack on the vice president as her being "a chameleon."

"I think he was observing the basic foundational reality that Kamala Harris pretends to be something different depending on which audience she's speaking to,” the senator said.

-ABC News' Hannah Demissie

Former President Donald Trump said he "couldn't believe" Vice President Kamala Harris picked Minnesota Gov. Tim Walz as her running mate, adding he "could not be more thrilled," when he called into Fox and Friends Wednesday morning.

"I would say my reaction is, I can't believe it. I never thought this was going to be the one that was picked," Trump said. "He's a very, very liberal man, and he's a shocking pick, and I'm thrilled. I could not be more thrilled."

Asked if his campaign thought Pennsylvania Gov. Josh Shapiro was going to be the VP pick, Trump said he thought Shapiro would've been a better choice.

"I would have said it would have been a better choice," Trump said of Shapiro. "I would have said others were the better, better choice."

-ABC News' Lalee Ibssa, Kelsey Walsh and Soorin Kim

Vice President Kamala Harris and Minnesota Gov. Tim Walz are scheduled Wednesday to hold rallies in Wisconsin and Michigan, bringing their "vision for the future" to two battleground states on their first full day of campaigning together.

"Together, they will highlight the choice facing Blue Wall voters between the Trump-Vance agenda to weaken unions and give tax cuts to the wealthy on the backs of the middle class, and the Harris-Walz vision for the future, where everyone has the opportunity not just to get by, but to get ahead," the Harris campaign said.

At their midday stop in Wisconsin, the pair will be joined by Gov. Tony Evers and Sen. Tammy Baldwin.

The pair will then travel to Wayne County Airport in Michigan for an evening rally, the campaign said. Gov. Gretchen Whitmer and Detroit Mayor Mike Duggan will join them, the campaign said.

"Their visits come on the heels of over a dozen labor endorsements, including last week's endorsement from UAW -- which represents more than 130,000 members in Michigan alone," the campaign said.

-ABC News' Gabriella Abdul-Hakim, Fritz Farrow and Will McDuffie