The dollars per vote in this year’s mayoral election, from $26 for Cherelle Parker to $460 for Allan Domb

Allan Domb and Jeff Brown dumped their own money into their mayoral campaigns. But they didn’t get much bang for their buck.

Domb, a former City Council member and a real estate magnate, gave more than $11 million of his own money to his campaign, and had nearly $460 in his war chest for every vote he received — the highest cost-per-vote of any mayoral candidate in recent city history. Brown, a grocer, gave his campaign $4 million, amassing about $300 per vote.

On the other end of the spectrum was Cherelle Parker, a former Council member who handily won the Democratic nomination. She raised about $26 for every vote she earned, the lowest among the top five candidates.

The results of the primary show that while wealthy, self-funding candidates can launch themselves into contention, their money isn’t necessarily decisive.

In all, Democratic candidates for Philadelphia mayor and the independent groups supporting them raised more than $34.6 million, the most expensive mayoral campaign in city history, according to an Inquirer analysis. With nearly 250,000 Democrats voting, that amounts to at least $145 for every vote cast in the primary election.

The Inquirer analysis focuses on money raised this election because more of that data has been reported than actual expenditures. Historically, the two are about equal once all amounts are reported.

This year’s more than $145 raised per vote far exceeds the $74 spent per vote in the 2015 Democratic mayoral primary and the $105 spent per vote in 2007. (Both figures are adjusted for inflation). It even exceeds the $81 spent per vote in last year’s high-profile Senate race in Pennsylvania, the second-most expensive general election Senate campaign in U.S. history.

Campaigns and PACs have two more weeks to report campaign finance data from the home stretch of the campaign, so this year’s totals will continue to grow.

The campaign was the most expensive in part because it was the most competitive in recent memory, with seven Democrats each attracting hundreds of thousands of dollars, at least, in donations. And it was just the second major mayoral primary since outside groups known as super PACs became legal. Super PACs aren’t subject to the city’s strict fundraising limits, but they cannot coordinate with the campaigns they support.

Another reason for the high dollar per vote is that fundraising surged but turnout did not. Fewer than a third of registered Democrats voted, just slightly higher turnout than in 2015.

“That’s a commentary on this election,” said Larry Ceisler, a public-affairs executive and longtime City Hall observer. “That for all these wonderful candidates and wonderful campaigns they ran and all the money that was spent, people just didn’t respond.”

The amount of money a candidate raises is an indicator of viability, and the contenders spend cash on operational needs such as staff, polling, offices, and campaign materials.

The largest expense, by far, is advertising, and one of the most effective ways to reach voters — television commercials — is pricey.

Candidates and super PACs spent more than $21.6 million on advertising, according to the media-tracking firm AdImpact. More than $17.7 million, or about 81%, was spent on TV.

The wealthiest candidates led the spending, with Domb pouring nearly $8.8 million into advertising and Brown spending more than $3 million on ads.

This year’s primary was unique in that it featured a deep field of candidates who came into the race with fundraising experience, donor bases, and viable paths to victory. Through the waning days of the campaign, no front-runners emerged in polling, so the spending blitz lasted through Election Day.

On top of that, all the top contenders — except Domb — were backed by super PACs, which became legal in Philadelphia after the 2010 Supreme Court decision in Citizens United.

The only other competitive mayoral campaign in the super PAC era so far was in 2015, when Jim Kenney decisively beat five Democratic opponents. Only he and State Sen. Anthony Hardy Williams were backed by super PACs, and none of the candidates that year were big self-funders.

The 2007 race had five serious contenders — but there were no super PACs, meaning the only spending was done by candidates subject to the city’s fundraising limits.

Primary elections for mayor in 2011 and 2019 each saw incumbent Democrats seeking the nomination, so they were far less competitive and attracted less cash.

In this year’s race, five super PACs raised $7.9 million, representing about 22% of the overall total. (Super PAC spending is not included in our dollar-per-vote analysis for each candidate.)

While Parker’s campaign raised over $2.1 million, a super PAC supporting her — largely funded by building-trades unions — raised another $2 million, allowing for her to compete on television with wealthy candidates.

The super PAC ran attack ads against several other contenders. Combined with other attack ads, that investment meant Parker was the only top candidate who was not the subject of negative ads in the final weeks.

Several other super PACs also played a prominent role. One supporting Gym raised $1.2 million, almost entirely from teachers’ unions.

Another, funded by a dark-money group, boosted Brown — until the city’s Board of Ethics accused the PAC of illegally coordinating with him. The group agreed in April to stop spending money to influence the outcome of the election, and the city’s lawsuit remains pending.

This year wasn’t the first time deep-pocketed candidates injected millions of their own dollars into an election.

In 2007, billionaire Tom Knox spent about $12.5 million of his own money on his mayoral campaign, or about $18 million in today’s dollars, only to come in second to Michael A. Nutter.

This year, Domb poured most of his $11 million into his campaign after January, when he triggered the city’s “millionaire’s amendment.” That provision doubles the city’s fundraising limits if any candidate spends $250,000 or more on their campaign.

Brown, a ShopRite proprietor and first-time candidate, gave more than $4 million of his own money to his the campaign.

Still, unlike Knox, who finished second in 2007 with about 70,000 votes, Domb and Brown finished at the bottom of the top tier of contenders, beating out only long-shot candidates. Brown weathered a series of negative headlines, but Domb did not suffer any major controversies.

In the end, Domb won about 28,000 votes, and Brown finished with about 22,000.

Some strategists say television advertising doesn’t have the sway in local elections that it once did. Others argue voters picked female candidates for an opportunity to elevate a woman in a city that has never elected a female mayor.

What was clear is that candidates struggled to compete unless they poured their own wealth into their campaigns or had a super PAC behind them. Political consultant Mustafa Rashed said conversations around public financing of elections could ramp up as lawmakers grapple with how to level the playing field.

“There’s a problem that there’s this much money in races,” he said, “but that’s just how it’s going to be because of campaign finance limits. It encourages this.”

Staff writer Sean Collins Walsh contributed to this article.