Del. Justin D. Ready, a Carroll County Republican and the interim executive director of the state GOP, said the party plans to put "resources toward working on a lawsuit" but noted "it costs a lot of money."

"It'll be a team effort," he said. "It'll be a point of emphasis for us as we raise funds, obviously."

Throughout the summer, Maryland Republicans and some members of the Legislative Black Caucus had hinted that they might join forces in opposing the governor's plan. Each of the three amendments offered by the GOP would have drawn three majority minority districts, a goal stated by some black leaders.

But none of the Black Caucus members voted with the GOP — including on a proposal drafted by the Fannie Lou Hamer group.

Ten Democrats, mostly from the Washington suburbs, supported a separate amendment that would have inched the new 4th District back into Montgomery County, a plan drafted by Rep. Donna Edwards. That plan failed 26-107.

In an unusual move, Edwards, a Prince George's County Democrat, spoke publicly against O'Malley's map on grounds that it would rob Montgomery, a majority minority county, of a black voice in Congress.

In a statement, Edwards acknowledged defeat, saying the state legislative process had "run its course." Still, she remains unhappy with the result, saying it "is not the best approach for minority voters or for all Marylanders."

O'Donnell offered the first of three GOP plans Wednesday — a proposal drafted this past summer by the state Republican Party that would keep congressional districts more compact. Democrats argued the GOP plan would force many voters into new districts.

Democrats, meanwhile, defended O'Malley's map, which they said would keep 70 percent of state residents in their current district. "There is no constitutional requirement that the map be pretty," said Del. Kathleen M. Dumais, a Montgomery County Democrat.

An alternate plan crafted by the Fannie Lou Hamer group initially appeared like it might gain some traction in the House, but it ultimately failed on a 40-97 vote.

The political action committee, named for the Mississippi-born civil rights leader in the 1950s and '60s, offered the map that would put Edwards' 4th District back into Montgomery County to ensure that minorities in that part of the state are represented by a black member of Congress.

It was introduced by Del. Neil C. Parrott, a freshman Republican best known for leading a successful effort to halt a law allowing some illegal immigrants to pay in-state tuition at Maryland colleges and universities.

But Baltimore County Del. Emmett C. Burns Jr., the pastor of an African-American church, rose to say he knew Hamer personally and attended her funeral. He gave an impassioned speech on the House floor, saying that he was "conflicted" about how his vote would affect minorities, but in the end supported the governor and said he believed Hamer would have too.

"I don't think I voted against her wishes," Burns said. "I think she would have opted for the larger picture, and that is more Democrats in the House of Representatives."