More than two million donations have been made to Sen. Bernie Sanders, I-Vermont, the campaign announced Wednesday.
A Twitter account representing campaign volunteers posted the milestone.
Sanders is also expected to receive the endorsement from the Communications Workers of America on Thursday, according to multiple reports. It's the largest communications and media union in the U.S., and represents more than 700,000 workers.
It would mark the third national union to endorse Sanders, who has already been endorsed by the American Postal Workers Union and National Nurses United. Hillary Clinton has secured the support of more union workers, however -- so far, she has 17 national labor endorsements, including the Service Employees International Union, and National Education Association.