In this May 29, 2018, file photo, President Donald Trump, left, and his daughter Ivanka Trump, right, watch as former football player Herschel Walker, center, throws a football during White House Sports and Fitness Day on the South Lawn of the White House in Washington. On Tuesday, Aug. 17, 2021, Walker filed paperwork to enter the U.S. Senate race in Georgia after months of speculation, joining other Republicans seeking to unseat Democratic Sen. Raphael Warnock in 2022. (AP Photo/Andrew Harnik, File)

ATLANTA (AP) โ€” Herschel Walker on Tuesday filed paperwork to run for U.S. Senate in Georgia after months of speculation, joining other Republicans seeking to unseat Democratic Sen. Raphael Warnock in 2022.

Walker, 59, joins the race with high name recognition, having won the Heisman Trophy in 1982 as a University of Georgia running back. Perhaps more important in todayโ€™s Republican Party, he carries the backing of former President Donald Trump.

Walker has never run for office and will likely face scrutiny over his turbulent personal history as well as policy stances. But if he emerges from the Republican primary, the Senate contest would feature two Black men vying for a seat in the heart of the Deep South.

Walker stayed mum Tuesday, continuing a pattern of few comments as he started to put a Senate bid in motion. He registered to vote last week, using an Atlanta residence owned by his wife, Julie Blanchard. Walker signed Federal Election Commission papers Tuesday declaring his candidacy, allowing him to raise money for a Senate run.

Republicans already running for the Senate seat include state Agriculture Commissioner Gary Black, former banking executive and Navy veteran Latham Saddler and contractor Kelvin King. Some other potential GOP candidates may not run with Walkerโ€™s entry into the race, including former Sen. Kelly Loeffler, who lost to Warnock in a January special election, and U.S. Rep. Buddy Carter, a four-term congressman from near Savannah.

Walker and Trumpโ€™s relationship dates back to the 1980s, when Walker played for a Trump-owned team in the short-lived United States Football League. Walker, who went on to play 12 seasons in the NFL, spoke in support of Trump at the 2020 Republican National Convention and later attended Trumpโ€™s private birthday celebration.

Trump has publicly encouraged Walker to enter the primary, telling a radio show in June that โ€œheโ€™s a great guy, heโ€™s a patriot and heโ€™s a very loyal person, heโ€™s a very strong person. They love him in Georgia, I tell you.โ€

With Trump the โ€œdefining figureโ€ in todayโ€™s GOP, University of Georgia political science Professor Charles Bullock said his backing might be all Walker needs.

โ€œIf he tells them they need to go out and vote for Herschel Walker, thatโ€™s the strongest endorsement he can possibly get,โ€ Bullock said.

Walkerโ€™s supporters hope he can reach moderate Republicans and peel off some traditionally Democratic African Americans. But the former presidentโ€™s support could be a liability in a general election in closely divided Georgia, where a crucial fraction of more affluent GOP voters defected to Democrat Joe Biden.

โ€œBy the end of this long, divisive, and expensive intra-party fight, itโ€™ll be clear that none of these candidates are focused on the issues that matter most to Georgians,โ€ Georgia Democratic Party spokesperson Dan Gottlieb said in a statement.

Walker could share a Republican ticket with Gov. Brian Kemp, a frequent target of Trump attacks, as Kemp seeks reelection. Trump has vowed vengeance against Kemp, saying he didnโ€™t do enough to overturn Trumpโ€™s election loss. Itโ€™s unclear if that enmity would damage Republican chances, with Democrats possibly fielding a united ticket of Warnock and Stacey Abrams. Walker endorsed Kemp, a fervent Georgia football fan, in Kempโ€™s 2018 victory over Abrams.

Warnock has already raised $10.5 million for the 2022 race but has downplayed Walkerโ€™s entry. Heโ€™s now traveling the state promoting a jobs agenda.

โ€œAnd I hear thereโ€™s a race next year,โ€ Warnock told the Atlanta Press Club last week when asked about Walker.

Black has tweaked Walker for his long absence from Georgia, and did so again Tuesday in a video โ€œwelcomingโ€ Walker to the race and challenging him to come to a Republican fish fry Saturday south of Macon.

โ€œI suppose Iโ€™ve always wanted an autograph,โ€ Black said, holding up a weathered football. โ€œBut there are some things that are far more important now: the future of our country, the future of our families.โ€

Sadler said in a statement that heโ€™s a better choice as a โ€œnext generation conservative leader who can beat Raphael Warnock.โ€

โ€œThis campaign isnโ€™t about the glories of yesterday; itโ€™s about our nationโ€™s future,โ€ Sadler said.

Walker has been living outside Dallas and is making his first run for office. Untested as a candidate, itโ€™s unclear whether he will be an adept campaigner or fundraiser, while also fleshing out positions on policy matters heโ€™s never had to address in detail. Walker has supported Trumpโ€™s baseless assertions that he was cheated out of reelection.

Walker also has a turbulent personal history that could factor into a campaign.

An Associated Press review of public records uncovered detailed accusations that Walker repeatedly threatened the life of his ex-wife, Cindy Grossman, by telling her relatives he would kill Grossman and her new boyfriend. Walker denied the accusations, but a judge granted a protective order in 2005 and for a time barred Walker from owning guns.

In 2008, Walker wrote a book that detailed his struggles with mental illness. He wrote that heโ€™d been diagnosed with dissociative identity disorder, once known as multiple personality disorder. He said he constructed alternate personalities as a defense against bullying he suffered as a stuttering, overweight child. Walker was raised in Wrightsville, 50 miles (80 kilometers) east of Macon.

Walker also wrote of playing Russian roulette with a gun at his kitchen table in 1991. Overall, Walker cast his story as a turnaround, saying he found a path to โ€œintegrationโ€ because of therapy and his Christian faith.

The book caused problems for one of Walkerโ€™s key business relationships. In a 2019 legal deposition, a manager for food distributor Sysco said the company almost cut ties with Walkerโ€™s poultry company, Renaissance Man Food Services, when the book created โ€œhavoc.โ€ Ultimately, Sysco stuck with Walkerโ€™s company until the controversy died down.

Walker has more recently made outsized claims about his business success. He repeatedly claimed his company employed hundreds of workers and grossed $70 million or more in annual sales.

But Walkerโ€™s company reported just eight employees when it applied for a federal Paycheck Protection Program loan last year. In a recent court case, Walker said his company averaged about $1.5 million a year in profit from 2008 to 2017.

State election officials opened an investigation into his wifeโ€™s residency after The Atlanta Journal-Constitution reported that records show Blanchard voted in Georgia despite living in Texas. Walker is among Trump supporters who continue to repeat the presidentโ€™s false claim that the 2020 election was stolen from him through fraud. Election officials nationwide found no widespread fraud.