The district encompasses the entire Eastern Shore of Maryland, as well as parts of Anne Arundel, Baltimore and Harford Counties, and was represented by Republican Wayne Gilchrest since 1991.

Harris entered the February 12 primary with endorsements from the Club for Growth,[3] former Governor Bob Ehrlich,[4] seven of ten state senators who represent parts of the Congressional district, and House minority leader Anthony J.

He defeated his closest opponent, Cambridge lawyer Christopher Robinson, by nine points in a primary that was considered much more civil than on the Republican side.

[9] In addition to targeting by the Democratic Congressional Campaign Committee,[10] Gilchrest staffers held "Republicans for Kratovil" events.

The Republican candidate is Richard Matthews, a 28-year-old computer systems engineer from Orchard Beach, who is also the Anne Arundel County, Maryland organizer for the Ron Paul 2008 Presidential campaign.

[15] Matthews is a moderate Republican with libertarian political views on civil liberties and economic freedom.

The district comprises portions of Prince George's and Montgomery Counties, and has been represented by Democrat Al Wynn since 1993.

He was challenged by Collins Bailey, a businessman and fourth-term elected member of the Charles County Board of Education.

Bartlett's district is one of the more Republican seats in heavily Democratic Maryland, and includes several western cities such as Frederick and Hagerstown.

In a surprise, former Cumberland Mayor Frank K. Nethken announced that he would be a candidate for the GOP nomination even if Bartlett sought re-election.

Van Hollen has achieved national prominence as head of the Democratic Congressional Campaign Committee.