In this Thursday, June 14, 2018, file photo, Amie Hoeber, right, a Republican who is running in the Maryland 6th Congressional District primary, talks to a supporter at an early voting center in Frederick, Md. (AP Photo/Brian Witte)
Jan Plotczyk, of Rock Hall, Md., joins a long line of people to get into a town hall with Maryland Rep. Andy Harris on Friday, March 31, 2017 at Chesapeake College in Wye Mills, Md. (AP Photo/Brian Witte)
Maryland Park Service rangers stand at the entrance to the exhibit hall of the Harriet Tubman Underground Railroad Visitor's Center before a media preview on Friday, March 10, 2017 in Church Creek, Md. (AP Photo/Brian Witte)
A bronze bust of Harriet Tubman, on display during a media preview of the Harriet Tubman Underground Railroad Visitor's Center on Friday, March 10, 2017, is one of the first things visitors see when entering the new facility in Church Creek, Md. (Brian Witte)
Angela Crenshaw, assistant manager of Harriet Tubman Underground Railroad State Park, talks about exhibits in the new visitor's center during a media preview on Friday, March 10, 2017 in Church Creek, Md. (AP Photo/Brian Witte)
In this Wednesday, April 20, 2016 photo, State Sen. Jamie Raskin, right, who is running in the Democratic primary for Maryland's 8th Congressional District, talks to a supporter who voted early for him, in Chevy Chase, Md. (AP Photo/Brian Witte)
Gov. Martin O'Malley, left, and Maryland Transportation Secretary Beverley Swaim-Staley discuss light rail projects while riding a MARC train in August 2009 (AP Photo/Brian Witte)