"Caucus...for Hillary," Ferrell says at one point in the video as he poses for pictures with fans.
— Hillary Clinton (@HillaryClinton) February 20, 2016
Ferrell was among the prominent entertainment industry figures backing Bernie Sanders in a list the campaign released in September, and is still among those named as endorsing the candidate on Sanders' website.
A Sanders campaign official did not immediately return a request for comment.
Clinton and Sanders are in what polls say may be a tight race for Saturday's caucuses, with results expected in the early afternoon.
Check out more from Hillary Clinton's campaign in the gallery below!