(Bloomberg) -- Joe Biden has attempted to brand himself as the most pro-labor president in US history. Workers who donate to the leading presidential candidates beg to differ.Republican frontrunner Donald Trump is winning financial support from grassroots campaign contributors who work for highly unionized workplaces, including American Airlines Group Inc. and  United Parcel Service Inc., according to Federal Election Commission data from the second half of 2023 analyzed by Bloomberg News.(1) He also has far more donors than Biden from people who report working for largely blue-collar workplaces, such as Walmart Inc. and Federal Express Corp.

That’s a symbolic blow to Biden who has staked his political identity as an advocate for blue-collar workers and the organized labor movement. It also could be a warning sign for his 2024 reelection bid that relies on winning heavily unionized states — Michigan, Wisconsin and Pennsylvania.

Biden has notched labor wins in recent weeks, including an endorsement from the United Auto Workers, but his campaign lags Trump in contributions from donors with oft-unionized job titles including mechanics and truckers, according to campaign finance records. Biden does better among workers who self-identify as professionals — including professors, scientists and psychologists —  who prefer him at rates of three-to-one or more over Trump.

Political donors represent a small fraction of voters, but those who give are some of the most motivated supporters. The Federal Election Commission doesn’t ask contributors whether they are in a union, but collects data on employers and job titles, which provides a proxy for political support among union members.  In an election that will likely feature two unpopular candidates, enthusiasm and turnout in key swing states will help make the difference.

Trump, who has yet to earn the endorsement of a major union, alluded to the divide between union leadership and membership after a meeting with the Teamsters in Washington last month, saying he wasn’t sure if the “top people” in the union will back him, but said he has “tremendous support” among the group members. 

Biden has spent much of his time recently courting the union vote: going to a UAW picket line in Michigan, visiting union halls and embedding pro-union requirements in incentives for clean energy policies. It’s possible Biden is starting to see that pay off. Donors who report being employed by General Motors Co.  and Ford Motor Co. — two companies that have been the subject of much of the president’s attention following last fall’s auto strike — are nearly evenly split between the two likely nominees.

Read More:  Swing-State Voters Blame Biden for Migrant Surge at the BorderBiden did beat Trump on donations from workers at some unionized businesses, including Kaiser Permanente and Boeing Co. 

Not every donor lists their employer or occupation, so contributions where these values weren’t reported were excluded from this analysis of companies and professions.

Biden and Trump tout their legions of working class donors who give small amounts, but over the second half of 2023, both relied heavily on billionaires and other wealthy donors who can write much bigger checks.

Two-thirds of Biden's fundraising haul over the last six months of 2023 — some $119 million — came from wealthy donors who gave to Biden Victory Fund, the Democratic National Committee and Future Forward PAC, his allied super political action committee. Billionaires Haim Saban and hedge fund manager George Soros, and entertainment mogul Casey Wasserman are among the major donors to Biden’s reelection effort.

Former South Carolina Governor Nikki Haley got a slightly bigger chunk (68%) of her money from large donations, including Citadel’s Ken Griffin, WhatsApp co-founder Jan Koum and Paul Singer of Elliot Investment Management.

Read More:  Singer Gives to Haley; Spielberg, Soros Back Biden for 2024 Even Trump drew 46% from mega-donors, including construction billionaire Diane Hendricks and Crownquest’s Timothy Dunn, who each gave $5 million. Home Depot co-founder Bernard Marcus gave $1 million. Trump drew 42% of his donations over the same period from contributors who gave $200 or less.

Biden slightly edges out his Republican rival in the number of unique donors who contributed to him in the final six months of last year, but Trump donors give to his campaign more frequently and in smaller amounts. Donors to the former president who contributed less than $200 at a time gave on four different occasions on average. Biden’s small-dollar donors contributed almost two-and-a-half times on average.

(1) Methodology Data includes donations received from July 1 to Dec. 31, 2023 and reported to the Federal Election Commission by the following committees: ActBlue, Biden For President, Biden Victory Fund, Biden Action Fund, the Democratic National Committee, the Democratic Grassroots Victory Committee and Future Forward PAC for donations to or supporting President Joe Biden; Donald J. Trump for President 2024, Make America Great Again PAC, Make America Great Again Inc., Save America, Trump Save America Joint Fundraising Committee for former President Donald Trump; Nikki Haley for President, Stand for America PAC, Team Stand for America and the SFA Fund Inc. for former South Carolina Governor Nikki Haley. Unique donors were identified by distinct combinations of first and last names, state and zip code. Company names and job titles were standardized where possible. For example, donors who list their employer as UPS and United Parcel Service were combined, as were lawyers and attorneys. Although employer and job title information is solicited from all donors, approximately 40% list these details. Contribution size categories are based on donation values rather than the total amount contributed by a unique donor. Because campaigns divide contributions greater than $3,300 into separate primary and general-election transactions, Bloomberg News' analysis also counts those donations made directly to campaigns in the $200–$3,300 category. Some contributions are not reported to the FEC. Donations under $200 made by mail or through online services other than ActBlue or WinRed don’t have to be disclosed. Totals in this analysis are based on contribution microdata published by the FEC and not the topline numbers reported to the FEC by each committee.

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