FARGO, N.D. (AP) — Another U.S. presidential hopeful has scheduled a campaign event in North Dakota.

Democrat Bernie Sanders is to appear at a Friday rally at the Ramada Fargo Convention Center, a day after three scheduled stops in South Dakota. Doors in Fargo open at 11 a.m. Admission is free and on a first come, first served basis.

Sanders is competing with Hillary Clinton for the Democratic endorsement. Whoever gets it likely will run against presumptive Republican nominee Donald Trump.

Trump is to address the Williston Basin Petroleum Conference at the Bismarck Event Center on May 26. There are 2,500 tickets available to the public, and The Bismarck Tribune reports they're a hot item. The 1,200 tickets available online sold almost immediately Monday, and people lined up at the box office Tuesday.