MACON, Ga. — Herschel Walker, the former football star leading Georgia’s Republican primary for Senate, had a mixed message about racial issues for 70 or so supporters, mainly white, who came to hear his stump speech this week at the Georgia Sports Hall of Fame.

He started with a joking aside — “I don’t know if you know this, but I’m Black” — before asking, “Where is this racism thing coming from?” Accusations of bigotry, he suggested, are often thrown around as a way to silence people like those in the crowd.

He did say that he had recently been called a racial slur, repeating the word and adding, “Can you believe that?” But, he went on, that was OK, because raccoons are smart animals, and the Bible does not talk about Black and white, just believers and nonbelievers.

The white members of the audience cheered. The few Black onlookers had a different reaction, wondering what race-blind Georgia he seemed to be referring to.

As Mr. Walker nears his coronation on Tuesday as the Republican nominee for one of Georgia’s Senate seats, it is clear that racial issues will be a major factor this fall, when he is all but certain to face Senator Raphael Warnock, the incumbent Democrat.

The contest between Mr. Warnock, a longtime civil rights champion, and Mr. Walker, whose ambivalence on the issue has long dogged him, is expected to be tight. Either way, Georgia will still have a Black senator. But just because both men are Black doesn’t mean race will be nullified as a factor.

“If anything, it could be put on steroids,” said Kevin Harris, an African American Democratic strategist active in Southern campaigns.

Mr. Walker is clearly sensitive about the subject. Asked how he would distinguish himself from Mr. Warnock, the pastor of Ebenezer Baptist Church in Atlanta, where the Rev. Dr. Martin Luther King Jr. once preached, Mr. Walker snapped: “Don’t say that. He’s running on separation.” He has struck similar themes in the past, arguing that civil rights leaders want the races divided.

White Republicans here welcomed Mr. Walker’s assurances that accusations of racism and injustice are all about division, when the nation needs unity.

George Jackson, who grew up in Mr. Walker’s hometown, Wrightsville, Ga., and went to high school with the candidate’s older brother, reassured his friends after the speech, “Herschel is not racist” — a signal that for some voters, racism by Black Americans, not by white ones, is the problem.

“Christ doesn’t look at race,” Kathy Peterson, 60, of Perry, Ga., who is white, said approvingly after the speech. “We’re all the same. We’ve been divided by the leadership we have now for too long.”

The few Black members of the audience, however, saw Mr. Walker’s longtime ties to Donald J. Trump — and the former president’s endorsement of him — as a red flag, and an indication that Mr. Walker was merely a vessel for the G.O.P. and Mr. Trump’s ambitions.

“I can’t get a brother from Wrightsville, Ga., jumping on the Trump campaign, you know?” Roderick McGee, 54, said at the Hall of Fame. “I can’t wrap my mind around that.”

He added, “He’s a puppet on a string, and somebody’s pulling those strings really good.”

Mr. Walker’s early years are a major part of his appeal. He loves to recount his days as a shy, bullied, “big-boned” — “which meant I was fat” — kid with a speech impediment, who took it upon himself to grow supremely athletic so he could stand up for himself.

He often riffs about what he calls an agonizing choice between joining the Marines or playing college football, then choosing a college as the most recruited high school athlete in the country.

Left unmentioned is another event from those days that Mr. Jackson readily offered up, a civil rights showdown in 1980 in little Wrightsville between the Black community and local law enforcement that brought Black leaders like Hosea Williams to town from Greater Atlanta, as well as Ku Klux Klansmen like J.B. Stoner.

Black local leaders wanted their most celebrated athlete to weigh in, but barely 18 and a high school senior debating his college choices, Mr. Walker stayed away.

“He said: ‘I don’t believe in race. I believe in right and wrong,’” Mr. Jackson, who is white, said approvingly.

Republicans hope Mr. Walker will peel away just enough Black votes from Mr. Warnock to take back a coveted seat in a Senate now divided 50-50. Driven by Mr. Trump’s quick endorsement, many in the party have looked past the football star’s history of domestic violence, his admitted struggles with mental illness, and his lack of political experience to chant his slogan: “Run, Herschel, run.”

Voters, Black and white, appeared aware of the stakes.

“This Senate race right here is going to be the most important race of them all,” said Darrell Robinson, 54, a Black man from Macon who attended the Walker event.

But it may not work the way the Republican establishment hopes. After the murders of George Floyd in Minneapolis and Ahmaud Arbery in Brunswick, Ga., 170 miles southeast of Macon, many Black voters are in no mood for the broad absolution of white people that Mr. Walker appears to be offering.

“People need to stop being afraid to have these hard conversations,” said LaTanja Taylor, 45, who was walking with a friend through downtown Macon. “That’s the only way we’re going to heal.”

As for Mr. Walker’s confidence that racism is not a problem, she quipped: “He’s blind. Something’s wrong with him.”

Celebrity might also not be the draw some think. Georgia’s booming population is young and includes many new arrivals to the state. To them, Mr. Walker’s Heisman Trophy in 1982 is ancient history. “I wasn’t even born then,” said Tiffany Clark, 38, Ms. Taylor’s friend, who laughed as she confessed she was not a sports fan and did not know who Mr. Walker was.

Ms. Clark, who is Black, said that her concern was health care for her aging parents, and that she liked Mr. Warnock’s efforts to expand the reach of health insurance in Georgia, despite successive Republican governors’ refusal to expand Medicaid under the Affordable Care Act. He has her vote, she said.

Mr. Warnock has been outspoken on racial issues, especially on voting rights. He castigated a restrictive voting law passed last year by Georgia’s Republican-led legislature, calling it racism in action.

“We are witnessing right now a massive and unabashed assault on voting rights and voter access unlike anything we have seen since the Jim Crow era,” he declared in a March 2021 Senate speech that ran through his state’s history of violent racial repression and its breakthrough civil rights moments.

Mr. Walker has taken a different path. At a hearing last year on reparations for the descendants of enslaved African Americans, he appeared remotely at the behest of Republicans.

He lamented, “We use Black power to create white guilt. My approach is biblical: How can I ask my heavenly father to forgive me if I can’t forgive my brother?” He continued: “My religion teaches togetherness. Reparations teach separation.”

At a rally in September with Mr. Trump in Perry, Ga., Mr. Walker told the crowd: “I’m going to tell you a secret. Don’t let the left try to fool you with this racism thing, that this country is racist.”

To some supporters, such assurances evince a warmth and understanding that could counter Mr. Warnock’s famous charisma. Phil Schaefer, a longtime football broadcaster at the University of Georgia, Mr. Walker’s alma mater, said: “I always felt there was something special in Herschel. There was a depth there that is now coming out.”

But Democrats see in Mr. Walker a political neophyte who is unprepared for the general election. In a difficult political year for Democrats, he could be a perfect foil for Mr. Warnock.

Mr. Harris, who helped engineer President Biden’s narrow victory in Georgia, said Republicans were so intent on recruiting a Black Senate candidate that they latched onto a man whose views on race will only alienate the Black voters they seek.

“He’s a flawed messenger,” Mr. Harris said, “but this is what you get when you’re not willing to do the work, and they don’t do the work on equity and inclusion. So they get Herschel Walker.”