U.S. Rep. Roscoe Bartlett is fighting to hang on to his seat after 20 years representing Western Maryland.

Two years ago the Sixth Congressional District was 47 percent Republican and 36 percent Democrat, data from the state Board of Elections show. After the state redrew the state’s congressional map in a once-a-decade redistricting process, the district lost Carroll, Howard and much of Frederick counties and gained part of liberal Montgomery County, becoming 44 percent Democrat and 33 percent Republican.