But few attendees likely realized that they were handing over their personal information to a private vendor that also works for Trump-linked political organizations. Campaign Nucleus—one of several firms owned by former Trump campaign official Brad Parscale—provided the forms used to register for high-profile semiquincentennial events this year.

Campaign Nucleus is one of various vendors with close ties to Trump’s campaign apparatus that was hired by Freedom 250, the group set up last year to help Trump control planning for the anniversary. Rushing to stage the kinds of high-profile events Trump wanted, the operatives running Freedom 250, who are themselves veterans of Trump campaigns, doled out large contracts to fellow MAGA insiders for event planning, public relations, and digital support. As Mother Jones has detailed, much of this was on American taxpayers’ dime.

Citing the cozy ties between annivesarry planners and GOP campaign efforts, House Democrats in a letter Tuesday asked the Government Accountability Office—the investigative arm of Congress—to examine whether pro-Trump political operatives have used data generated from the anniversary events to help Republicans in November.