U.S. Senate candidate Herschel Walker has directly tied himself to Donald Trump as often as he can, touting the former president’s endorsement and support for his policies at his campaign appearances.

But the sharpest divide between the two political allies might be their stances on immigration, an issue that has long polarized conservatives and seems certain to gain traction as the 2022 vote nears.

Walker, a political newcomer who gained fame playing football, was one of Trump’s earliest supporters during the 2016 race for the White House. But even then, he expressed caution over the presidential candidate’s hard-line stance on unauthorized immigrants.

He told USA Today in August 2015 that he supports Trump’s idea of building a wall along the U.S. border with Mexico but disagreed with his plan to deport millions of immigrants living in the country illegally. He also said then that he’d back a proposal that enables such immigrants to earn citizenship.

In a statement to The Atlanta Journal-Constitution, Walker’s campaign didn’t disavow his previous comments about opposing Trump’s deportation policy or his endorsement of an immigration overhaul that would grant a path to citizenship for millions.

Instead, campaign spokeswoman Mallory Blount said Walker supports those who follow the legal process to enter the country and highlighted the “humanitarian and illegal immigration crisis at our southern border that career politicians have created.”

“When you have a leak, you fix it,” she said. “Any conversations about immigration have to start with finally securing our southern border, and Herschel will work to make that happen.”

Walker is the most prominent Republican challenging Democratic U.S. Sen. Raphael Warnock in next year’s election, which could decide control of the Senate.

Georgia Republicans have increasingly emphasized tough immigration stances as President Joe Biden’s administration struggles with a surge of migrant crossings. They hope the issue can unite a fractious conservative base torn by Trump’s attacks on state Republican leaders who refused to overturn the 2020 presidential election.

U.S. immigration agents have apprehended more than 1.5 million unauthorized migrants along the southern border since last October. That’s the most in more than two decades.

Earlier this month, Gov. Brian Kemp trekked to the U.S. border with Mexico to assail Biden’s immigration policies and call for a crackdown on illegal crossings. And Agriculture Commissioner Gary Black, Walker’s best known GOP rival, said he saw “utter chaos” when he went to the border a few days later.

“We’re devastated, but we’re going to solve this problem,” Black said. “Georgians, I will help solve this problem, but it’s going to take one more conservative vote in the U.S. Senate.”

Black’s campaign on Monday sharply critical of Walker’s immigration approach.

“Herschel Walker’s immigration policy is like an illegitimate love child of Mitt Romney and Nancy Pelosi,” said spokesman Dan McLagan, invoking two politicians reviled by many Georgia Republicans. “Republicans are going to throw up in their mouths a little when they hear about it.”

Walker has offered few specifics about his stances on policies since entering the race in August, but he told Fox News last week that securing the border is among his top priorities.

“I don’t care whether you’re Democrat or Republican, I’m here to represent you,” he said. “Because everything that the Democrats want, I guarantee it is what I want. We want law and order. We want the border patrolled. We want prices to go down.”