Former President Trump's running mate, Sen. JD Vance, R-Ohio, will travel to the key swing state of Arizona Thursday, where he plans to visit the southern border.

Vance will make an appearance in a critical state for the Trump campaign’s hopes of winning the election while also tackling a critical concern of voters in the race by visiting the border, Fox News Digital has learned.

The border stop comes as the Trump campaign has pivoted to running against Vice President Kamala Harris, who was elevated to the top of the ticket after President Biden’s decision to drop out of the race last week.

HOW LONG WILL THE HARRIS ‘HONEYMOON’ IN THE POLLS LAST?

JD Vance peaking at the RNC

Sen. JD Vance speaks during the Republican National Convention in Milwaukee, Wisconsin, on July 17, 2024. (Al Drago/Bloomberg via Getty Images)

Trump and Vance have made it a priority to highlight how Harris has contributed to many of the unpopular policies of the current administration, particularly the vice president’s role in attempting to identify and solve the "root causes" of illegal migration at the southern U.S. border that resulted in the vice president being labeled the administration's "border czar."

Vance sought to highlight the issue the day after Biden’s decision, arguing in remarks to reporters that Harris’ position at the top of the Democratic ticket didn’t change the "political calculus" for the Trump campaign.

"We were running against Joe Biden’s open border, Kamala Harris’s open border. Kamala Harris supported the green new scam. Kamala Harris, frankly, covered Joe Biden even though it was obvious he was mentally incompetent for a very long time," Vance said at the time.

Kamala Harris at podium

Vice President Kamala Harris speaks during a campaign event at Westover High School in Fayetteville, North Carolina, on July 18, 2024. (Allison Joyce/AFP via Getty Images)

WHAT THE LATEST FOX NEWS POLLING IN THE KEY BATTLEGROUNDS SHOWS 

Vance expressed a similar sentiment in a meeting with donors in Minnesota Monday, arguing the campaign had a "unique opportunity" to highlight Harris’ record on the border now that she has emerged as the nominee.

Polls have continued to show that immigration and border security are at the top of mind of voters as they get ready to head to the polls in November, even as the record number of illegal crossings of the last few years has waned since peaking in December.

Migrants detained by authorities near border

Migrants are apprehended near the border wall in New Mexico on April 12, 2024. (Fox News)

WHAT THE LATEST FOX NEWS POLLING IN THE KEY BATTLEGROUNDS SHOWS 

Those concerns were highlighted in a Gallup poll released last week, with 55% of U.S. adults wanting to see immigration levels reduced, the first time in nearly two decades that Americans have expressed a preference for less immigration. Meanwhile, 25% of respondents said they would like to see immigration numbers stay at the present level and 16% said they would like to see immigration levels increase.

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