CHARLOTTE, N.C. — In his first campaign event since the presidential race was upended, former President Trump didn't waste any time in trying to define his new opponent.

At a rally in the crucial battleground state of North Carolina, the Republican presidential nominee repeatedly took aim at Vice President Kamala Harris, whom he derogatorily called "lying Kamala Harris."

Harris has succeeded her boss, President Biden, as the presumptive Democratic Party nominee after Biden — in a blockbuster announcement on Sunday — dropped his re-election bid and endorsed his vice president.

TRUMP HOLDS FIRST RALLY AFTER 2024 PRESIDENTIAL RACE TRANSFORMED

Kamala Harris

Vice President and Democratic presidential candidate Kamala Harris speaks at West Allis Central High School during her first campaign rally in Milwaukee on Tuesday. (Kamil Krzaczynski/AFP via Getty Images)

The embattled president's immediate backing of Harris ignited a surge of endorsements of Harris by Democratic governors, senators, House members and other party leaders. By Monday night, the vice president announced that she had locked up her party's nomination by landing the backing of a majority of the nearly 4,000 delegates to next month's Democratic National Convention. She has also hauled in a staggering $129 million since Biden's announcement, her campaign touted on Thursday morning.

IT'S A MARGIN OF ERROR RACE BETWEEN TRUMP AND HARRIS 

Trump, speaking to a packed arena in Charlotte, aimed to paint Harris as the "most incompetent and far-left vice president in American history."

Trump charged that Harris "has been the ultra-liberal driving force behind every single Biden catastrophe. She is a radical left lunatic who will destroy our country if she ever gets the chance to get into office." 

Donald Trump aims to define Kamala Harris before she can define herself

Former President Donald Trump speaks at a campaign rally in Charlotte, North Carolina, on Wednesday. (AP Photo/Alex Brandon)

And pointing to Sen. Bernie Sanders of Vermont, the far-left champion and two-time runner-up for the Democratic presidential nomination, Trump argued that Harris is "more liberal than Bernie Sanders. Can you believe it?"

Throughout his more than an hour and a half stream of comments, Trump repeatedly slammed the vice president over border security and crime, two top issues in the 2024 election.

The strategy by Trump, his campaign and allied groups, is simple: Define Harris, who is not nearly as well known to Americans as Trump and Biden, before Harris has the chance to define herself.

Trump campaign spokesman and senior adviser Steven Cheung said that the former president's team was ready to go on offense the moment Harris succeeded Biden as the Democrats' standard-bearer.

"There wasn’t any surprise. We were prepared for it. We had all our assets ready. We had all our content ready. It didn’t surprise anyone," Cheung told reporters ahead of the Trump rally.

Former President Donald Trump criticizes Vice President Kamala Harris at a rally in North Carolina

Former President Trump, the GOP presidential nominee, headlines a rally in Charlotte, North Carolina, on Wednesday.  (Fox News - Paul Steinhauser)

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."

Kochel, a veteran of numerous GOP presidential campaigns who remained neutral in the 2024 Republican primary, noted to Fox News that "Trump’s got a big megaphone."

He offered that Trump's slights are "not without merit," as he noted that Harris "did run to the left of Biden" in the 2020 Democratic presidential nomination race and that "she had one of the most liberal records in the Senate when she was there."

Harris is 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.

Harris speaks at the White House

Vice President Kamala Harris speaks from the South Lawn of the White House in Washington, D.C., on Monday, during an event with NCAA college athletes. (AP Photo/Susan Walsh)

"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 Monday at an event at her campaign headquarters in Wilmington, Delaware.

"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.

Harris repeated the line of attack the next day at a rally in Milwaukee.

Trump responded at Wednesday's rally, saying, "I don’t think people are going to buy it." And he argued that the vice president "was one of the worst prosecutors in history" and that "she destroyed San Francisco."

The former president touted his support for law enforcement and landed the backing of the National Association of Police Organizations, as the group's president, Michael McHale, joined Trump on the podium to formally endorse the GOP nominee.

The Harris campaign panned Trump's performance, with spokesman Ammar Moussa calling it "an unhinged, weird and rambling speech" and arguing that "the American people won’t be fooled or distracted" by Trump's salvos.

The jabs by Trump come as Harris is in the process of taking full control of the Biden campaign, cementing her nomination, which will formally come as early as next week during a virtual roll call ahead of the Democratic National Convention, and choosing a running mate by early next month.

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While Harris is enjoying plenty of earned media during this seemingly honeymoon phase of her fledgling campaign, when it comes to paid media, the Trump campaign and its aligned groups currently have a massive advantage.

Trump's air superiority will likely be short-lived, as the Harris campaign appears to be working to produce and air spots as soon as possible.

"She needs to be on the air with some pretty compelling bio stuff," Kochel emphasized.

Ahead of the rally, Republican National Committee Chair Michael Whatley said that even though Trump is now facing a new opponent at the top of the Democrats' ticket, the GOP's strategy "does not change … at all."

"We have been running our race, and we are going to continue to run our race," Whatley, a former North Carolina GOP chair whom Trump installed as RNC chair in March after clinching the Republican nomination, emphasized in a Fox News interview.

Whatley, speaking at the rally site at Charlotte's Bojangles Coliseum, noted that Trump and the RNC will relentlessly tie Harris to Biden's policies on border security, fighting inflation, crime and other top issues in the 2024 election.

"The Democrats not only have a messenger problem, they have a message problem. And Kamala Harris is doubling down on every single one of Joe Biden's failed policies. It's the Biden-Harris administration, the Biden-Harris campaign. And she is picking up that mantle," Whatley argued.

Fox News' Mark Meredith and Jennifer Johnson contributed to this report.

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