Six Philadelphia elected officials who are considering 2023 mayoral campaigns reported impressive fund-raising totals in highly anticipated financial disclosures this week, marking the unofficial start of the race to replace outgoing Mayor Jim Kenney.

But it was a report filed with the state, not the city, that most surprised Philadelphia’s political class and created uncertainty about the 2023 election. A political action committee with ties to Jeff Brown, the owner of several ShopRite grocery stores who has publicly flirted with a mayoral bid, took in a jaw-dropping $934,000 last year.

Much of the cash raised by Philly Progress PAC came from donations well in excess of Philadelphia’s campaign contribution limits. A statement from the group provided by political consultant Jimmy Cauley — whom Brown reportedly hired to work on his potential 2023 campaign and was paid $210,000 by Philly Progress — said it doesn’t endorse candidates.

Brown didn’t respond to a request for comment on the PAC, which also paid his son $26,000. Cauley said that Brown “has been involved with Philly Progress and has been incredibly helpful with fund-raising,” but that it’s not a campaign-in-waiting for him.

The other potential candidates include five City Council members, who each hauled in more than $200,000 last year, and City Controller Rebecca Rhynhart, who raised $549,000 while coasting to reelection.

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It’s unlikely that all those positioning themselves to run will ultimately do so — in no small part because of the city’s “resign to run” rule, which requires officeholders to step down from their positions once they begin campaigning for new elected office.

But the financial reports are the clearest indication yet of who is serious about the 2023 Democratic primary. The winner is all but guaranteed to win the general election thanks to the party’s more than 7-1 voter registration advantage in the city.

The Council members eyeing the race are Allan Domb, Derek S. Green, Helen Gym, Cherelle L. Parker, and Maria Quiñones-Sánchez. Their 2021 fund-raising hauls ranged from Quiñones-Sánchez’s $204,000 to Domb’s $359,000.

They took in hundreds of relatively small checks to comply with strict city limits on donations, which are $3,100 per calendar year for individuals and $12,600 from businesses or political committees.

Philly Progress PAC, meanwhile, took in checks of $100,000 each from Hotwire Communications LTD of Fort Lauderdale, Fla., and Westville Investments LLC of Westville, N.J. The group reported that it was seeking to influence the 2021 general election. But it did not list any candidates it supported, and it carried more than $445,000 into 2022.

Cauley initially said the group was a nonprofit but later clarified that it was not registered as a nonprofit.

“Philly Progress PAC is dedicated to the serious problems that plague our City and the enormous possibilities of our future,” the group said.

Brown is “just one of many leaders who has been helpful” raising money for the PAC, Cauley said. He said that Brown hired him through Philly Progress and that he doesn’t work for Brown in any other capacity.

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Adam Bonin, a Philadelphia-based election lawyer, said that much of the PAC’s spending — like payments to political consultants, a pollster, an opposition research firm, and the local Democratic Party — are the types of expenditures he would expect from a candidate preparing a campaign.

If the PAC is helping Brown explore a mayoral run, Bonin said, it must be “rigorous” about how it uses money that came from donations exceeding city limits. Spending for purely exploratory purposes, such as polling Brown’s popularity, would pass legal muster, he said. But “front-loading campaign expenses” could result in an investigation by the city Board of Ethics.

“Most people would be surprised that you can raise and spend money toward what sure seems like a mayoral campaign without complying with the city limits,” he said. “This is a known exception to Philadelphia campaign finance law, but you have to be very careful with it.”

While the Council members raised less than Brown and Rhynhart, their hauls were notable for officials who were not up for reelection.

Still, they have a long way to go to match the resources that went into Kenney’s 2015 victory, in the last open mayoral race. His campaign spent about $1.8 million. Outside groups backing him that were largely funded by labor unions spent more than $3 million.

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Mayoral aspirants will also have to show they have a path to victory and a vision that will resonate across the city. Some may be vying for similar constituencies.

Brown and Domb, for instance, are both wealthy white businessmen who would likely emphasize their managerial experience and records on racial justice issues. Brown is well-known for hiring formerly incarcerated employees in his stores, and Domb has cast his push to cut the wage tax as a way to make the city’s regressive tax structure less burdensome for working-class families.

Domb, a real estate magnate, is the wealthiest member of Council and can help fund his own campaign.

“I haven’t made a decision about whether to run for Mayor, but I have been encouraged by the support I’ve received,” said Domb, whose campaign had $300,000 in the bank going into 2022. “If I think I can do something to help Philadelphia at this time of crisis — and make no mistake, our city is in a crisis — I will run.”

He and Brown aren’t the only would-be candidates who could complicate each other’s calculations. Both Parker and Green hail from the Northwest Coalition, the storied Black political organization that controls wards with some of the highest voter turnout rates in the city.

But the pair of ex-aides to former Councilmember Marian Tasco have also crafted distinct brands on Council. Parker has championed bread-and-butter neighborhood issues like cleaning up commercial corridors, while Green has worked to make the city more business-friendly and pushed ethics reform.

Green, who raised $279,000 last year and finished with $207,000, said that he is “definitely seriously considering” running for mayor.

A source close to Parker, Council’s majority leader, confirmed she’s also considering a run. Parker took in $255,000, including donations of $3,100 each from Gov. Tom Wolf and his wife, placing her in the middle of the Council pack. She had $218,000 at the end of the year.

Quiñones-Sánchez also got her start in Tasco’s office, although she forged her own path to office, winning four Council elections as an independent-minded Democrat without the help of the party.

“Given what the 2023 primary is going to look like, my belief is [the winner] is going to be a woman, and it’s going to be a woman of color, and therefore when I look at the field I consider myself one of the top two folks,” said Quiñones-Sánchez, who finished the year with $218,000.

Many of the mayoral hopefuls have worked to promote progressive policy goals. But if she runs, Gym will undoubtedly have the backing of the city’s activist progressive movement, which has helped secure victories such as the election of Larry Krasner as district attorney.

Gym raised $285,000 in 2021 and finished the year with $327,000 in the bank, the most of any Council member. Brendan McPhillips, her campaign manager, said Gym’s “fundraising success is a reflection of the grassroots support she has across the city for consistently delivering results for working families.”

“Helen’s deeply proud of the work she’s been able to accomplish on council that’s making a real impact in people’s lives,” McPhillips said.

McPhillips said Gym, who was rumored to be considering a run for Congress, will not seek federal office in 2022.

Rhynhart, whose office is tasked with auditing city finances and investigating fraud, hasn’t served as a lawmaker, and it’s less clear how voters will perceive her. A former investment banker who left Wall Street to work in city government, Rhynhart has emphasized her financial acumen and a pragmatic approach to social justice issues.

She had $769,000 in the bank at the end of the year, the most of any of the mayoral hopefuls.

“I want to have the biggest impact I can have on the city, but I’m focused on my job,” Rhynhart said. “There’s a lot of issues in the city right now.”