The Supreme Court late Friday agreed to hear a challenge to the lines of a Maryland congressional district that were drawn by Democrats.  

The court has already heard a partisan gerrymandering case from Wisconsin, where Republicans drew the state legislative map. 

In the Maryland case, the plaintiffs are challenging the congressional map enacted by the Maryland General Assembly after the 2010 Census, arguing that it’s a partisan gerrymander that favors the Democrats. 

At issue is the state’s 6th District, which has been represented by a Democrat since the 2011 redistricting. Longtime GOP Rep. Roscoe G. Bartlett lost his 2012 re-election to Democrat John Delaney by more than 20 points after winning the seat fairly easily since 1992. 

Some legal experts had expected the Supreme Court to hold off on hearing this case while the Wisconsin case is pending. But the challenge in Wisconsin is to the entire legislative map, whereas in Maryland, the challenge applies only to the 6th District lines. 

In both cases, the court postponed the question of whether or not it has jurisdiction until the hearing of the cases. 

Maryland’s 6th District will be an open seat in 2018. Delaney is vacating the seat to run for president in 2020. Republicans have identified the district as a pickup opportunity. Inside Elections with Nathan L. Gonzales rates the race Solid Democratic.