In a ruling that could have major implications for next year's congressional elections, a North Carolina court late Monday struck down the state GOP's 2020 legislative district map on the grounds that it was unlawfully gerrymandered to favor the Republican Party.

"Extreme partisan gerrymandering—namely redistricting plans that entrench politicians in power, that evince a fundamental distrust of voters by serving the self-interest of political parties over the public good, and that dilute and devalue votes of some citizens compared to others—is contrary to the fundamental right of North Carolina citizens to have elections conducted freely and honestly to ascertain, fairly and truthfully, the will of the people,” the three-judge panel wrote in its 20-page ruling (pdf).

Politico reporter Jake Sherman said the decision is "potentially seismic for control of Congress."

Progressive advocacy groups and voting rights advocates celebrated the court's ruling as a major victory for democracy.

"This is huge," tweeted Stand Up America. "NC is one of the most gerrymandered states in the country."

Echoing Stand Up, Mother Jones journalist Ari Berman called the court's ruling a "big deal" and pointed to the significant advantage the Republican Party had under the gerrymandered map:

The North Carolina court's ruling came months after the right-wing Supreme Court ruled in June that partisan gerrymandering is beyond the constitutional reach of federal courts, a decision voting rights advocates decried as an abdication of responsibility that could open the door to more extreme partisan gerrymandering in the future.

As HuffPost reported Monday, "despite that decision, the five-justice majority at the Supreme Court said that state courts and state constitutions may be able to act against gerrymandering."

"Advocates now believe that bringing suits in state court may be the most effective legal strategy for combatting gerrymandering," HuffPost noted.