The U.S. Supreme Court on Friday added a second case to its docket on a contentious issue that could have major consequences for American elections, agreeing to decide whether Democratic lawmakers in Maryland unlawfully drew a congressional district in a way that would prevent a Republican candidate from winning.

The court's agreement to take up an appeal by Republican voters in Maryland regarding the U.S. House of Representatives district came two months after the justices heard arguments in a high-profile challenge by Democratic voters to Republican-drawn state legislative districts in Wisconsin.

Both cases target a practice known as partisan gerrymandering that aims to entrench one party in power and that critics have called a distortion of the democratic process. The justices have not yet issued a ruling in the Wisconsin case.

(Reporting by Lawrence Hurley; Editing by Will Dunham)