ATLANTA - Standing in front of a crowd of over 10,000 people in battleground Georgia's capital and largest city, Vice President Kamala Harris went on offense over an issue that she and President Biden have been playing plenty of defense over the past couple of years.

Harris, near the top of her 18-minute speech, took aim at former President Trump over the issue of border security, which many Republicans see as the vice president's political Achilles heel.

"In this campaign I will proudly put my record against his," Harris said, before highlighting her border security efforts as California attorney general.

Harris argued that Trump, the Republican presidential nominee, "has been talking a big game about securing our border, but he does not walk the walk."

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She pointed to a border security bill with some bipartisan support that was making its way through Congress earlier this year before Republicans turned against the measure after prompting from Trump.

"It was all set to pass, but at the last minute Trump directed his allies in the Senate to vote it down," Harris said. 

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She charged that the former president "tanked the bipartisan deal because he thought it would help him win an election" and pledged that "as the president I will bring back the border security bill that Donald Trump killed."

Trump, his campaign and allied groups have repeatedly criticized Harris over the past week and a half - since she replaced Biden at the top of the Democrats' national ticket - over the surge of migrants across 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.

The Harris campaign says they are not scared to pick a fight over immigration and border security.

However, Trump campaign national press secretary Karoline Leavitt told Fox News that they "relish the opportunity" to "go head-to-head" with Harris over the issue.

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The Trump campaign quickly took to social media to respond to the comments by the vice president at her rally.

"Kamala is actually *BRAGGING* about her record on immigration. HERE ARE THE FACTS: As Border Czar, Kamala ferried 15+ million illegals directly into our communities. She thinks illegal immigration "is NOT a crime." She wants to abolish ICE. She thinks you're stupid," the Trump campaign claimed.

Hours earlier, the Trump campaign - in its first major ad blitz of the general election - charged that Harris had "failed us" in securing the border.

Responding to the ad, Harris campaign spokesperson Ammar Moussa reiterated the theme that Trump had a heavy hand in "killing the toughest border deal in decades."

"As a former district attorney, attorney general, and now vice president, Kamala Harris has spent her career taking on and prosecuting violent criminals and making our communities safer. She'll do the same as president," Moussa emphasized.

As the vice president was arriving at the Georgia State Convocation Center in downtown Atlanta - the same venue where Trump and his running mate Sen. JD Vance will hold a rally on Saturday - the Harris campaign put up a new video that spotlights border security. 

The video argued that Harris "helped lead the way to record low border crossings and has spent her entire career keeping our communities safe" and charged that Trump "sided with drug traffickers and the cartels to block the strongest, fairest reforms to secure the border in decades."

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The Trump campaign instantly pilloried the video.

"Every statement in Kamala’s border ad is an absolute lie. The truth is that President Trump handed the most secure border in history to the Biden-Harris Administration, and they opened it up by erasing every one of his good policies," the Trump campaign charged. "As Border Czar, Kamala Harris has overseen the worst immigration crisis in American history, enabling drug cartels to smuggle deadly fentanyl across our border and allowing more than 11 million illegal criminals and terrorists from all over the world to enter our country. "

Vance - at two stops in Nevada on Tuesday - turned up the volume on his attacks on Harris over border security. In Reno, he pledged that "in six months, we're going to re-elect Donald J. Trump, president of the United States. And when we do, we're going to launch the largest deportation program in American history. If you came here illegally, you got to go back."

On Thursday, Vance will hold a campaign event in Arizona along the U.S.-Mexico border.

The Democratic National Committee, in response to Vance's comments, fired off an email titled "JD Vance Doesn’t Care About Border Security – He Followed Trump’s Orders to "Kill" Bipartisan Border Deal."

Picking a fight on border security may not seem to some like a smart strategy for the vice president's team.

However, a Harris campaign official told Fox News that they are not scared to go on offense on immigration and on the border and charged that Trump does not have any credibility on the issue.

The Trump campaign is happy to have the fight.

"We relish the opportunity for President Trump, who created the most secure border in history, to go head-to-head with failed Border Czar Kamala Harris, who has overseen the worst border crisis in history," Leavitt argued. "On the issue of immigration in every single poll, President Trump dominates Harris because Americans know the truth about their records."

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