The group Republican Voters Against Trump is kicking off its spring ad blitz with its inaugural ad airing Friday in swing states around the country, aiming to highlight the former president’s soured relationship with Vice President Pence.

“Mike Pence knows Donald Trump better than anyone else and he knows how dangerous a second Donald Trump administration would be,” the speaker in the ad says. “Mike Pence is putting country over party.”

The advertisement is set to air in Arizona, Michigan, Georgia, Pennsylvania, and Wisconsin and will be accompanied by billboards outside Phoenix, Atlanta, Detroit, Grand Rapids, Philadelphia, Pittsburgh, and Milwaukee. 

Republican Voters Against Trump, which first surfaced in 2020, is the brainchild of a prominent anti-Trump Republican, Sarah Longwell, alongside a conservative writer, William Kristol, and a former aide to Governor Bush, Tim Miller.

A strategist for the group, John Conway, tells the Sun that the ad is the first of a $50 million campaign that the organization plans to ramp up in the spring. He says that this first stint of the campaign was a “six-figure spend.”

“Mike Pence is now a Republican voter against Trump,” Mr. Conway tells the Sun. “He served the administration for four years, but he understands that another Trump presidency would be dangerous for America.”

Mr. Pence launched his own bid for the Republican nomination but failed to gain traction and dropped out in October. Last week, the former vice president said that he wouldn’t be endorsing the former president in the 2024 elections, telling Fox News: “It should come as no surprise.”

Mr. Pence and President Trump had a falling out in the wake of the January 6, 2021, storming of  the Capitol, when a cry of “hang Mike Pence” was heard from the mass of Mr. Trump’s supporters. 

Mr. Trump had previously waged a pressure campaign on Mr. Pence in an attempt to get the vice president to not certify the 2020 election results. Mr. Pence refused to comply, citing his constitutional duty.

Mr. Pence may be the most high-profile Republican to refuse to fall behind the former president after Mr. Trump rolled through the GOP primary early this year.

Other top Republicans with strained relationships with the former president, like Senator McConnell, have come out in favor of the former president. Governor Haley, who recently ended her presidential campaign, has declined so far to say if she will endorse Mr. Trump. 

“I’m incredibly proud of the record of our administration,” Mr. Pence told Fox News of his decision. “But that being said, during my presidential campaign, I made it clear there were profound differences between me and President Trump on a range of issues. And not just our differences on our constitutional duties that I exercised on January 6.”

While it’s not clear that Mr. Pence retains much influence in either the party or among Republican voters, Mr. Conway highlighted how Mr. Pence’s refusal to support Mr. Trump could serve as a permission structure for some voters to break with him.

“If Mike Pence can be a Republican voter against Trump, they can too,” Mr. Conway says.