PHILADELPHIA — Democrat Gov. Tim Walz is not a household name outside his home state of Minnesota.

So, in the hours after Vice President Harris named the former longtime congressman and two-term governor as her running mate on the Democratic Party’s 2024 ticket, the Harris campaign instantly began working to showcase Walz.

His biography was blasted out on social media platforms, including Instagram and X, formerly known as Twitter, and the Harris campaign spotlighted the governor in a new video.

And the vice president and Walz on Tuesday evening, in Pennsylvania’s largest city, kicked off a jam-packed campaign swing through the key battleground states that will likely determine the outcome of their 2024 election matchup against former President Trump and his running mate, Sen. JD Vance of Ohio.

VICE PRESIDENT HARRIS NAMES MINNESOTA GOV TIM WALZ AS HER RUNNING MATE

The campaign said that the rally drew over 14,000 people into the Liacouras Center at Temple University. The figure included the overflow crowd that wasn’t able to make into the arena.

The introduction to Walz is needed because 7 in 10 Americans didn’t know enough about the governor to form an opinion, according to a new poll by Marist College for NPR and “PBS NewsHour.”

As she boarded Air Force Two on her way to Philadelphia, Harris said Walz “is going to make a great vice president” when asked why she chose him over some of the other front-runners in the veepstakes: Pennsylvania Gov. Josh Shapiro and Sen. Mark Kelly of Arizona. 

Shapiro, who arrived to a loud and sustained standing ovation, spotlighted to the hometown crowd that “every single day I go to work for you” and that “I focus on getting sh-t done for all of you,” which elicited loud cheers.

And pointing to the Minnesota governor, Shapiro also said to cheers that “Tim Walz is a great man. Tim Walz is an outstanding governor…and I’ll tell you something else, Tim Walz is a dear friend.”

Walz returned the compliment later in the rally when he spoke, telling the crowd “what a treasure you have in Josh Shapiro.”

WHAT THE TRUMP CAMPAIGN SAYS ABOUT KAMALA HARRIS’ NEW RUNNING MATE

The Harris campaign on Tuesday evening said it hauled in more than $20 million from grassroots supporters in the hours after the vice president announced her running mate, which it said was “one of the campaign’s best fundraising days this cycle.”

The naming of the 60-year-old Walz was not a shocker as his name was instantly thought to be in contention in the 16 days since Harris succeeded President Biden as the party’s standard-bearer.

Walz, a former high school teacher and coach who spent nearly a quarter-century in the National Guard, was elected to the House in 2006 and re-elected five times. He represented Minnesota’s 1st Congressional District, a mostly rural district covering the southern part of the state.

Having the plainspoken Walz on the national ticket not only helps Harris in Minnesota – a state that leans blue in presidential elections that the Trump campaign has been aiming to flip this year – it also benefits the vice president in the two neighboring Midwestern battlegrounds of Wisconsin and Michigan.

WHO IS TIM WALZ? MEET THE HARRIS RUNNING MATE WHO CALLED REPUBLICANS ‘WEIRD PEOPLE’

The governor will also be able to showcase a slew of progressive policy victories in Minnesota, including protecting abortion rights, legalizing recreational marijuana, and restricting gun access to curb shootings. And the naming of Walz over more moderate Democrats such as Shapiro and Kelly will please the progressive wing of the party.

“As a governor, a coach, a teacher and a veteran, he’s delivered for working families like his,” Harris said in announcing her choice.

Harris said “one of the things that stood out to me about Tim is how his convictions on fighting for middle class families run deep.”

“It’s personal,” she said. “He grew up in a small town in Nebraska, spending summers working on his family’s farm. His father died of cancer when he was 19, and his family relied on Social Security survivor benefit checks to make ends meet. At 17, he enlisted in the National Guard, serving for 24 years. He used his GI Bill benefits to go to college and become a teacher.” 

And at the rally, Harris pointed to the synergy with her running mate, saying “Coach Walz and I may hail from different corners of this great country. But our values are the same….We both believe in lifting people up, not knocking them down.”

Harris repeatedly referred to Walz as “coach” as she highlighted his teaching and football coaching career. She also noted that the governor was the “highest-ranking enlisted man to ever serve in” Congress and that he “was known as one of Capitol Hill’s best marksmen.”

Walz, in his speech, noted that “for 24 years I proudly wore the uniform of this nation” and spotlighted that he and his siblings followed in their father’s footsteps in becoming educators.

He also threw out some zingers at the Republican ticket, including spotlighting Trump’s numerous court cases and legal entanglements. “Make no mistake, violent crime was up under Donald Trump, and that doesn’t even count the crimes he committed!” Walz said.

And pointing to Vance, he said “I can’t wait to debate the guy…that is if he’s willing to get off the couch and show up.”

And he repeated his line that Trump and Vance “are creepy and just weird.”

It was a very different take from the Trump campaign, which instantly targeted Walz.

“Kamala Harris just doubled down on her radical vision for America for tapping another left-wing extremist as her VP nominee,” the moderator in a new Trump campaign video charged. “Tim Walz will be a rubber stamp for Kamala’s dangerous liberal agenda.”

And Vance, who was in Philadelphia hours before the Democrat ticket arrived, called Walz’s record as governor “a joke” and said he was “one of the most far-left radicals in the entire United States government at any level.”

Vance is tailing Harris and Walz with small-scale events this week as they hold rallies in key swing states.

As the Harris-Walz rally concluded, the Democratic National Committee announced that the running mates had been officially certified as the party’s 2024 nominees.

Harris, near the top of her comments at the rally, pointed to her formal winning of the DNC’s virtual roll call of delegates to the upcoming convention, saying to cheers that “I am now officially the Democratic nominee.”

Get the latest updates from the 2024 campaign trail, exclusive interviews and more at our Fox News Digital election hub.