Former U.S. Sen. David Perdue formally qualified to challenge Gov. Brian Kemp in the GOP primary Wednesday, sealing his decision by declaring that he is the only Republican who can unite the party’s base against Democrat Stacey Abrams.

Speaking to reporters after filling out the paperwork, Perdue downplayed his struggles in polls and fundraising and said his campaign is “right where we want to be right now.” The pro-Donald Trump backlash against Kemp, he predicted, won’t soon abate.

“I just don’t see how Brian is going to pull together all the Republican Party to stand up against Stacey. They’re too upset about too many things right now,” Perdue said. “I believe, based on what we did in 2020, I’m the guy that can pull us together.”

Perdue was ousted in a 2021 runoff by Jon Ossoff in one half of a Democratic sweep that flipped control of the chamber. Rather than seek a return to the U.S. Senate, Perdue challenged Kemp in December with Trump’s blessing.

Once a top ally of Trump’s in the U.S. Senate, Perdue launched his campaign with a near-total focus on the former president, who has vowed to defeat Kemp for refusing to illegally overturn his election loss in Georgia. But in recent weeks, Perdue has expanded his message to try to peel off more of Kemp’s backers.

He’s promised to repeal the state income tax, which accounts for $14 billion in state revenue. He’s embraced the stalled attempt to carve out a new Buckhead city from Atlanta. And, most recently, he’s attacked the $5 billion proposed Rivian plant as a financial boondoggle.

Kemp has retained his advantage. He leads Perdue by roughly 10 percentage points in recent public polls, and he’s reserved roughly $5 million worth of airtime through the May 24 primary. That’s about five times more money than Perdue has collected since entering the race in December.

The governor is also wielding his office’s far-reaching powers to reinforce his conservative credentials. In recent weeks, he named a protégé of U.S. Supreme Court Justice Clarence Thomas to Georgia’s highest court and cleared the way for Sonny Perdue — David Perdue’s first cousin — to lead the state’s higher education system.

“At this point, David Perdue’s campaign is nothing more than an in-kind contribution to Stacey Abrams,” said Kemp spokesman Cody Hall. “While the former senator continues to run a failing campaign, Governor Kemp will remain focused on uniting Republicans behind a record of results and beating Abrams this fall.”

But Perdue has reinforcements on the way. Trump is hosting a fundraiser next week at his Mar-a-Lago estate for the candidate, and the former president is expected to stage a rally for Perdue later this month. On Monday, Donald Trump Jr. headlined a Cumming event that drew hundreds to Perdue’s banner.

“We need people who will actually fight back, people who aren’t just going to kowtow to the establishment on both sides, people who will actually fight for the America First agenda,” the younger Trump said. “We’re going to do a lot more for him.”

Kemp hasn’t shrunk from the challenge, agreeing to a slate of four debates with Perdue across the state. After weeks of silence, Perdue said Wednesday that “you’d better bet” that he’ll square off against the incumbent.

“I love being the challenger,” he said. “I want this governor to answer a lot of questions.”