RALEIGH, N.C. — A state court on Monday blocked the use of current congressional districts in North Carolina for the 2020 election, which could lead to the drawing of new districts that would make several of the Republican-held districts far more competitive.

The state’s House delegation is made up of 10 Republicans and three Democrats, but many of the GOP-leaning districts rely on the same strategies the court rejected in a previous case about state legislative seats, including splitting Democratic strongholds in some parts of the state while packing as many Democratic voters as possible into other districts.

Drawing new House districts could spell more difficulty for either Rep. Mark Meadows or Rep. Patrick T. McHenry, Republicans who split voters in Asheville, a rapidly growing left-leaning city in the western region of the state. It could also shake up the districts surrounding the state’s high-growth urban regions.

Before the 2012 election cycle, the first to use new maps drawn after the last census, the state’s congressional delegation included seven Democrats and six Republicans. But Republicans won control of the legislature in 2010 and drew new maps in 2012 that favored their party.

In the 2018 elections, all three winning Democrats won their districts with 70 percent or more of the vote while only one only Republican, who was unopposed, received more than 60 percent of the vote.

The filing period for the 2020 candidates opens Dec. 2.

Redistricting advocates took to state courts this year in the wake of a Supreme Court decision in June that partisan gerrymandering was a matter for state courts to decide.

A three-judge panel in Wake County Superior Court last month ordered North Carolina’s state legislative districts to be redrawn after ruling that partisan gerrymandering violated the state constitution. That same panel approved the new legislative districts on Monday and, in a separate ruling, blocked the use of the current congressional districts.

The case is backed by the National Democratic Redistricting Committee, led by former attorney general Eric Holder.

Attorneys for the plaintiffs in the congressional case hailed the injunction, calling it both a sign that they are likely to prevail in an upcoming trial and an indication that the court is committed to ensuring new maps for the next election.

“North Carolina’s congressional districts are easily the most gerrymandered in the country. The decision proves that, despite the Supreme Court’s ruling from this past June, courts can remedy partisan gerrymandering,” said Elisabeth Theodore, a partner with Arnold & Porter. “The court recognized that democracy is too important to wait. Every single congressional election in North Carolina this decade has proceeded under unconstitutional maps. Now at least North Carolina’s voters will get one chance to vote in fair congressional elections.”

Theodore said plaintiffs would quickly file a motion for summary judgment in the case.

State Senate leader Phil Berger (R), who has criticized Holder for his state redistricting initiatives, said the decision underlines the importance of state court races. “With judges deciding behind closed doors how many Members of Congress from each party is acceptable, judicial elections have become the most consequential in America,” Berger said in a statement.

The congressional maps were redrawn in 2016 after a successful challenge in federal court over racial gerrymandering.

A spokesman for House Speaker Tim Moore (R) said Moore was reviewing the order.

Bob Phillips, executive director of Common Cause North Carolina, which is a plaintiff in both the state legislature and the congressional cases, said the injunction is a welcome victory.

“We hope it is a sign that the state’s egregiously gerrymandered congressional districts will ultimately be struck down and redrawn to be completely free from partisan gerrymandering,” Phillips said. “As the landmark ruling in Common Cause v. Lewis made clear last month, partisan gerrymandering violates the constitutional rights of North Carolina voters and it must end.”

In an interview with the News & Observer of Raleigh last week, Rep. George Holding (R), who represents part of Wake County, said he expected the districts to change and had altered his fundraising strategies as a result. In his latest campaign finance report, Holding reported raising less than $100 from residents of his current district.