Philadelphia, Pennsylvania - Vice presidential nominees JD Vance and Tim Walz are on the offensive as the 2024 presidential race heats up.

On Tuesday, Democratic candidate Kamala Harris unveiled Walz as her pick for a running mate, sending a shockwave of excitement throughout the party.

While on a plane heading to Philadelphia for a rally, his Republican counterpart Vance shared his reaction with CNN, describing the pairing as an "interesting tag team" because Walz "allowed rioters to burn down Minnesota" following the murder of George Floyd, and Harris "bailed out" the alleged rioters.

During his speech at the Philadelphia Arena, Vance then described Walz as "one of the most far-left radicals" in government, and accused Harris of bending "the knee to the most radical elements of her party."

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He was, notably, not joined by his boss, Donald Trump.

Vance went on to do an interview with Fox News later that night, further explaining why he believed Harris choosing Walz was a "shameful" decision.

"He's a really far-left candidate. He's a really far-left governor, but the fact that Kamala Harris selected him, I think, shows really, really poor judgment and that she doesn't have what it takes to be President of the United States," Vance argued.

"This decision... is another sign that she doesn't care what the American people think," he added.

That same evening, Walz joined Harris on stage at Girard College, only four miles away from Vance's event, at a huge rally to celebrate their ticket.

While both Democrats focused their speeches on selling their visions of America, Walz did manage to sneak in a few jabs aimed at Vance.

"Like all regular people in America's heartland, JD Vance studied at Yale, had his career funded by Silicon Valley billionaires, and wrote a bestseller trashing that community," Walz told the crowd at one point.

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"Come on! That's not what middle America is," he continued.

"I can't wait to debate the guy – that is, if he's willing to get off the couch and show up!" Walz joked, referencing a false social media rumor that Vance once had sex with a couch.

Trump had previously agreed to debates with President Joe Biden, but after Harris took over as the Democratic nominee, he has insisted that they debate only on Fox News.