A new academic study estimates Republican fundraisers lost $117 million last year because Google, Microsoft, and Yahoo’s email systems flagged GOP fundraising messages as spam while letting Democratic fundraising emails through cleanly.
The study comes from Dr. Cameron Ellis of the University of Iowa and Dr. Lars Powell of the University of Alabama. The New York Post reports the two researchers used itemized Federal Election Commission donation records to separate first-time donors from repeat donors on the Republican platform WinRed and the Democratic platform ActBlue, then tracked donation patterns during two periods of spam filtering last year.
The first period ran from June 30, 2025, when GOP consulting firm Targeted Victory alerted Google that WinRed emails were landing in spam, through September 15, 2025, when Google dropped a spam blacklist called SURBL that the researchers say had wrongly flagged the messages. During that stretch, spam filtering cut first-time WinRed donations by 75 percent across Gmail, Outlook, and Yahoo. A second period, limited to Outlook and running from February through April of last year, saw first-time WinRed donations fall 83 percent.
Combined, the two periods cost Republicans an estimated 142,126 first-time donations. Using FEC data, the researchers converted that shortfall into $117 million.
“It’s a pretty big number,” Powell told the Post. He said the loss functioned as a windfall for the other side: “You can really think of that as an in-kind gift to ActBlue recipients.”
Ellis and Powell wrote that “a narrow, link-level placement decision by a small number of mailbox providers produced a measurable and economically meaningful drop in political fundraising, and that the mechanism was observable only because private paired-test evidence leaked into public reporting.”
Powell acknowledged the difficulty of studying systems the companies keep closed. “We can’t read their minds,” he said, but pointed to supporting evidence: “Inbox placement data and paired email tests showed when the filtering happened and supported that WinRed links were the trigger.”
Once Google stopped using SURBL on September 15, the researchers found GOP email placement “normalized.”
For context: the RNC, NRCC, and NRSC raised $377 million combined in 2025. Gmail alone has more than 3 billion monthly users.
Google Pushes Back
A Google spokesperson said the study “relies on deeply flawed methodology that fundamentally misunderstands how Gmail works” and dismissed the $117 million figure as a theoretical estimate rather than a real-world number. “Our spam protections apply equally to everyone, regardless of political affiliation and we encourage bulk senders to follow best practices to reach inboxes,” the spokesperson said, adding that “people are in full control of their inboxes, with the power to mark messages as spam, block senders, or unsubscribe at any time.”
Microsoft declined to comment. Yahoo did not respond to a request for comment.
The findings build on earlier reporting from Targeted Victory, whose clients include Rep. Steve Scalise (R-LA), Sen. Marsha Blackburn (R-TN), and the National Republican Senatorial Committee. The firm’s tests sent identical emails through Gmail, differing only in whether they contained a WinRed or ActBlue donation link. Emails with WinRed links were consistently flagged as suspicious or dangerous; those with ActBlue links went through without issue.
Google changed Gmail’s settings that August. A new “verified sender program” that lets political campaigns and PACs bypass Gmail’s spam filters, provided they stay “policy-compliant,” takes effect Tuesday.
Powell said he has had no contact with Google about the study but offered a theory for why the company acted anyway. “They make money by having people send more emails. If people start changing, that’s bad for their business model,” he said. “I think that’s when we find out whether they’re more blue or green.”
Bernadette Breslin, press secretary for the National Republican Senatorial Committee, said, “Google’s biased algorithms sidelined Republican fundraising emails for years while boosting Democrats’ donor outreach.” She added, “The NRSC has helped lead the investigation into Google’s suppression of mail to conservative subscribers, and this long-overdue update is a chance to level the playing field for online fundraising.”
A GOP adviser who has followed the spam filter issue called the study a “massive proof point in what we already knew to be true,” and a “smoking gun that con[firms]” the pattern.
