When Democrats in Annapolis redrew Maryland's congressional district maps, they hoped to make the 6th District, centered on Western Maryland, more competitive. At that, they succeeded. Rep. Roscoe Bartlett, the longtime Republican incumbent, suddenly finds himself in a district that includes a major portion of Democrat-rich Montgomery County. Although the new lines were evidently drawn with Democratic state Sen. Rob Garagiola in mind, the race has attracted significant competition in both parties.