(Bloomberg) -- Donald Trump’s back on Facebook, but the technology giant’s data changes are hobbling his ability to wring cash from its users as effectively as he did during his astonishing rise to the White House.

Trump, who has raised more money online than any other politician, no longer can directly target his tens of millions of Facebook followers with fundraising appeals, nor can he find users who have similar political views, making it harder and more expensive to prospect for contributors. While these changes affect every grassroots campaign that relies on Facebook to raise money — including progressives like Alexandria Ocasio-Cortez, who in 2018 upset a veteran New York congressman — the former president needs to grow his army of small-dollar donors more than ever.

On Friday, Trump’s “I’M BACK” post on the platform was his first since 2021 and followed the lifting of his suspension in January. Facebook’s parent,  Meta Platforms Inc., had barred him from his accounts for two years for encouraging his supporters to march on the US Capitol on Jan. 6, 2021.  It's a sign that he's reaching for a familiar and once-potent tool as he plans his 2024 comeback.

But the terrain has changed, and the 2024 race will be the first time presidential campaigns will grapple with the loss of Facebook’s political data. Trump, who’s also facing a possible indictment by New York prosecutors over hush payments to actress Stormy Daniels, spent 91 cents to raise each dollar in the roughly six weeks after he declared his third presidential run, an unsustainable return on investment. And he needs to find millions more contributors who give $10 or $20 at a time, since many deep-pocketed GOP donors, including Interactive Brokers Group Inc. founder Thomas Peterffy and Blackstone’s Steve Schwarzman, have said they won’t support him this time. 

Other once-loyal donors, like billionaire Miriam Adelson, said they plan to sit out the nomination battle, where Trump faces several likely challengers, including Florida Governor Ron DeSantis as well as his former vice president, Mike Pence, who enjoy the support of wealthy benefactors.

The ad-targeting options, which first began to disappear in January 2022, were gone by April. Already as a result of the changes, partisan ad spending on Facebook has plummeted, a Bloomberg News analysis of NYU Ad Observatory data shows. Spending by incumbent House candidates decreased by 40% in 2022 from 2020, and there was less political ad spending on Facebook at the start of this year than any other on record.

“Campaigns and the industry associated with it got very dependent on Facebook ads,” said Eric Wilson, a Republican digital strategist. “Those times are gone, just like 0% interest rates.”

The elimination of these options to locate ideal targets is particularly stinging for Trump, who since 2015 has raised more than $1.2 billion from small-dollar donors, much of it with the help of the social media platform. Many of those donors give only once, and of those who give multiple times, more than half stop giving within 90 days of their first contribution, a Bloomberg analysis of Federal Election Commission data shows.The Trump campaign didn’t comment for this article.

The predicament for candidates underscores the immense power Facebook — which 52% of US voters log into daily— can wield through the trove of data it collects on its users and how it chooses to share it. Because political ad revenue makes up only a tiny fraction of Facebook’s overall take, campaigns aren’t a key market segment for the tech giant.

“They don’t react to the small, almost granular needs of any kind of campaign, and especially a grassroots campaign,” said Chris Nolan, founder of Spot-On, a bipartisan ad-buying firm.

A spokesman for Meta Platforms Inc. declined to comment. In November 2021,  a company blog post announced the changes, citing user expectations as well as concerns raised by civil rights experts, policymakers and others on “preventing advertisers from abusing the targeting options we make available.”

A win for privacy advocates is raising the costs for those hoping to be the next Ocasio-Cortez, who built a grassroots movement online and trounced a 10-term member of the Democratic leadership. In her 2018 primary challenge, Ocasio-Cortez raised more than $568,000 while spending just $76,750 on Facebook ads— her only fundraising expenditure, an analysis of federal records shows. It cost her less than 14 cents to raise a dollar.

The Squad Victory Fund, which frequently runs ads on Facebook and raises money for Ocasio-Cortez and her progressive colleagues, saw its fundraising cost increase by a third, to 50 cents a dollar in 2022 from 2020. Representatives for the fund didn’t return a request for comment, and Ocasio-Cortez’s campaign declined to comment.The loss of political targeting information will make it harder for political campaigns, including Trump's, to raise money, said a person familiar with the former president's fundraising operation. 

Trump’s campaign has been trying out alternatives such as YouTube and even Snapchat, the app known for disappearing photo messages, federal records show. The campaign is also focusing more on email and text messages as it retools its voter outreach, said the person close to the campaign, who asked not to be named when discussing internal matters.

Before the Facebook changes, campaigners could target users based on their interactions with political and social issues, and then show them ads in line with their leanings, digital fundraisers said. And they could reach people who were more politically engaged than the average Facebook user. They could also direct appeals to, say, supporters of the National Rifle Association, or of Planned Parenthood. It’s why campaigns spent $885 million on the platform in 2020.

Having lost access to political data, campaigns can only tap less pertinent metrics on users, such as age, location, gender and general interests, fundraisers said. But most are unlikely to be sufficiently passionate about politics to donate to any candidate.

With targeting now more akin to broadcast television ads, prospecting for donors on Facebook is much less efficient, said Kari Chisholm, founder and president of Mandate Media, a Democratic online advertising and fundraising firm.

“We’re wasting our money on people who don’t care about politics and don’t want to see these ads,” Chisholm said.

Other factors have contributed to the declining effectiveness of finding donors on Facebook, digital ad buyers said. The company imposed a temporary ban on almost all political advertising in the aftermath of the 2020 election. That was later extended to March 2021 following the Jan. 6 attack on the US Capitol by Trump supporters whipped up by his false claims of election fraud. And in the wake of the 2016 election, Facebook, which was accused of letting disinformation foment on its platform, downplayed political posts in users’ timelines.

On Friday, Trump tried to rekindle the feelings of that campaign, when Facebook provided most of the $250 million he raised online. In the 12-second video he posted on the platform from his 2016 election night victory speech, he said, "Sorry to keep you waiting, complicated business.”

--With assistance from Laura Davison.

©2023 Bloomberg L.P.