Three federal judges on Tuesday expressed doubt that Maryland's new congressional map was drawn with the intent of undermining the voting power of minorities, as nine black voters have charged in a lawsuit against the map.

Instead, it appears the mapmakers' intent was rooted in protecting some congressional incumbents, said Judge Paul V. Niemeyer, one of the three judges who reviewed the lawsuit in U.S. District Court in Greenbelt.

"If that is the motivation, it is hard to get racial discrimination out of that evidence," Niemeyer said.

The lawsuit claims that Maryland's growing population of black, Asian and Hispanic groups justifies the creation of a third minority-majority district.

It also says that the redrawn districts deliberately dilute blacks' voting power statewide "for the benefit of white candidates."

Jason Torchinsky, an attorney for the plaintiffs, specifically targeted Democratic Rep. Steny Hoyer's district, which remained largely unchanged by the redistricting process.

He said the Democratically controlled legislature could have added more black voters to Hoyer's district but decided not to in order to protect him from a black challenger.

The Maryland General Assembly approved the map during a special legislative session in October. The Maryland Republican Party and black activists have teamed up in their opposition to the map and to one change in particular, which would attach a hefty portion of the Democratic-leaning Montgomery County to the solidly Republican congressional 6th District in Western Maryland.

Assistant Attorney General Daniel Friedman defended the map's intent in District Court.

"It is impossible for me to believe that the main purpose of the map was infected by racism," Friedman said. "If that were the case, the entire African-American leadership in the state of Maryland was hoodwinked. I don't believe that happened."

The judges did not make any rulings or specify when they plan to make a final decision. The state is urging the judges to make a decision before the Maryland State Board of Elections' candidacy filing deadline, which is Jan. 11, so the state can hold its primary on April 3, as planned.

The suit is expected to cost the plaintiffs a quarter-million dollars, according to Radamese Cabrera, spokesman for the Fannie Lou Hamer Political Action Committee, a black-majority voters rights group that helped mobilize the plaintiffs.

This is the second lawsuit filed against Maryland's new congressional map.

The first, brought by Smithsburg resident Howard Gorrell, claims the new districts illegally lump together Western Maryland's farming communities with urbanized areas of Montgomery County.

Gov. Martin O'Malley has scheduled a hearing in Annapolis on Thursday on his newly proposed legislative redistricting map.