Harris, Trump camps launch dueling ad blitzes to define VP for voters

The crucial race to define Vice President Kamala Harris is accelerating, with the campaigns of Harris and former President Trump both dishing out big bucks to run ads that aim to harden voters' perceptions of the vice president.

The commercial by Harris – her first since President Biden dropped his 2024 re-election bid and endorsed his vice president nine days ago – is titled "Fearless" and spotlights her years as San Francisco district attorney and California attorney general.

"As a prosecutor, she put murderers and abusers behind bars. As California’s attorney general, she went after the big banks and won $20 billion for homeowners," the narrator in the spot says.

And pointing to her three and a half years as vice president, the narrator spotlights that Harris "took on the big drug companies to cap the cost of insulin for seniors. Because Kamala Harris has always known who she represents."

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Trump's ad – part of the Republican presidential nominee's first major ad buy since the beginning of the year during the GOP primaries – targets Harris for being weak on border security, which along with crime is a leading issue on the minds of American voters.

"She’s failed us. Under Harris, over 10 million illegally here. A quarter of a million Americans dead from fentanyl. Brutal migrant crimes. And ISIS – now here," the narrator argues.

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The ad includes a clip of Harris' well-watched and widely criticized interview in 2021 with NBC News in which she pushed back against a question about whether she had visited the nation's southern border with Mexico.

"Kamala Harris. failed, weak, dangerously liberal," the narrator charges.

Trump's campaign says it will spend over $12 million to run the ad for the next two weeks in the key battleground states of Arizona, Georgia, Michigan, Nevada, Pennsylvania and Wisconsin.

It amplifies Trump and his campaign's attacks on Harris over the past week over the surge of migrants over the nation's southern border during the Biden administration.

Harris was tasked by Biden in 2021 with leading the diplomatic outreach to tackle the "root causes" of migration in Central American countries. It led to her being dubbed the "border czar" both by the media and Republican opponents, although the White House has rejected that description.

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The former president's campaign comes as two pro-Trump super PACs, MAGA Inc. and Preserve America, are running multimillion-dollar ad blitzes that also criticize Harris over border security.

The Harris campaign says its first TV commercial – which uses clips from her first rally last week, in Milwaukee, Wisconsin – is part of a $50 million ad buy on local and national broadcast TV, cable, streaming and social channels, ahead of the Democratic National Convention, which kicks off Aug. 19 in Chicago.

The narrator in the Harris spot claims that "Donald Trump wants to take our country backward," which appears to be a move by the 59-year-old vice president to spotlight the 78-year-old Trump's age.

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Biden's blockbuster announcement nine days ago came amid mounting pressure from within the Democratic Party for him to drop out after a disastrous performance in last month's first presidential debate with Trump. The 81-year-old Biden's halting and stumbling delivery fueled questions about his physical and mental abilities to serve another four years in the White House.

But Biden's immediate backing of Harris ignited a surge of endorsements for the vice president by Democratic governors, senators, House members and other party leaders. Within 36 hours, Harris announced that she had locked up her party's nomination by landing the verbal backing of a majority of the nearly 4,000 convention delegates.

The switch at the top of the Democratic Party ticket upended the presidential race, which was a rematch between two candidates who were extremely well known to Americans.

But the vice president is not nearly as well known to voters, and both the Harris and Trump campaigns are aiming to be the first to define her.

"Kamala Harris has always stood up to bullies, criminals and special interests on behalf of the American people – and she’s beaten them," Harris campaign chair Jen O'Malley Dillon said in a statement accompanying the ad's release.

For over a week, Harris has been pointing to her hefty law enforcement résumé as she spotlights Trump's numerous legal controversies, including his 34 felony convictions two months ago in the first criminal trial of a former or current president.

"As many of you know, before I was elected as vice president, before I was elected as a United States senator, I was the elected attorney general of California. Before that, I was a courtroom prosecutor. In those roles, I took on perpetrators of all kinds," Harris said at a campaign event last week.

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"Predators who abused women, fraudsters who ripped off consumers, cheaters who broke the rules for their own gain. So, hear me when I say I know Donald Trump’s type," she emphasized as she pointed to Trump's multiple lawsuits and criminal cases, many of which are ongoing.

Trump pushed back at a rally last week in Charlotte, North Carolina. 

"I don’t think people are going to buy it." Trump emphasized, as he argued that the vice president "was one of the worst prosecutors in history" and that "she destroyed San Francisco."

And in an interview Monday on Fox News' "The Ingraham Angle," the former president reiterated his charge that Harris is far more liberal than Biden.

Longtime Republican consultant David Kochel emphasized that both the Trump and Harris campaigns are "in a race to define" the vice president and that most Americans "know so little about her record… It’s go-time for both sides."

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

Fox News Digital's Adam Shaw contributed to this report