This post has been updated with other experts weighing in on the implications of the North Carolina case on other gerrymandering cases.

This year, federal courts have been litigating a steady stream of gerrymandering claims. And most of the electoral maps the courts have knocked down were drawn by Republicans.

That’s good news for Democrats: They have an opportunity in several states to draw more favorable congressional and state legislative maps ahead of 2018 elections. And every seat counts, given the 2020 Census is right around the corner, which brings with it the opportunity in many states to draw new district maps.

Some Republican legislatures are paying the price for capturing 21 chambers in the 2010 elections, the last time electoral maps were being drawn. Monday, North Carolina became the third GOP-controlled state legislature in a row to get its map-drawing skills declared illegal by the Supreme Court.

What’s more, some gerrymandering experts think the court ruled against North Carolina Republicans in a way that opens the door for Democrats to potentially challenge almost all mapmaking in the South.

Here’s a rundown of the redistricting landscape — and how it could affect our elections.

May: The Supreme Court throws out North Carolina’s GOP-drawn congressional map

The Supreme Court ruled Monday that North Carolina’s GOP-controlled legislature illegally looked at people’s race when drawing two majority-black congressional districts in the state.

Lawmakers argued they were only looking at drawing lines based on people’s party affiliation, but the court ruled that it is reasonable to assume that, in a state like North Carolina, party affiliation and race are pretty much synonymous.

The way the court arrived at its decision is a big deal, said Doug Johnson, a redistricting expert with Claremont McKenna College. “It’s the first time the court has used party as a proxy for race,” he said. “It opens the door to throwing out partisan gerrymandering as well.”

Other gerrymandering experts disagree that this decision has any implications for partisan gerrymandering. "This is a traditional case about racial gerrymandering, pure and simple," said Rick Pildes, an expert on redistricting law at New York University.

North Carolina Republicans held their 10 to 3 lock on congressional districts. But the court could now have a different way of reviewing yet another upcoming case in North Carolina, where legislators explicitly said they were drawing lines based on politics, and in Maryland, the lone pending gerrymandering case where Democrats drew the map.

March: Supreme Court questions Virginia GOP-drawn state legislative maps

When the justices looked at Virginia’s state legislative maps in March, the Supreme Court didn’t say whether they thought the state’s GOP-controlled legislature had illegally drawn districts to group together African American voters (and dilute their impact across the state).

Instead, they told a lower court to take another look at whether Republicans illegally drew their maps. As The Washington Post’s Robert Barnes and Gregory S. Schneider wrote at the time, “The decision was a win for black voters and Democrats.”

Virginia state elections are in the fall, and all 100 state House seats are up. It’s unclear whether the legal challenges will finish in time to require the redrawing of maps.

But Virginia also brings with it a reminder that map changes do have consequences: In November, Democrats picked up a seat here after the 4th Congressional District was redrawn for — you guessed it — being illegally gerrymandered.

Also in March: Three congressional districts in Texas get struck down

A federal court decided that Texas’s legislature intentionally tried to disenfranchise minority voters when it drew its congressional districts in 2011.

The court threw out three districts — two of which are held by Republicans. Any redrawing will likely give Democrats and Latino voters more say here, which could make an Austin-area district held by Rep. Lloyd Doggett (D) more blue and a swing district along the border even more difficult for Rep. Will Hurd (R) to hold onto. (Hurd won it by less than a percentage point in November.)

This isn’t the first time that Texas has been legal trouble regarding voting rights. A federal court also recently found that a 2011 Texas voter ID law discriminated against minorities.

Two strikes could force Texas back under the supervision of federal officials, who would review any election changes Texas wants to make. A 2013 Supreme Court ruling invalidating a key part of the Voting Rights Act freed Texas and other Southern states from federal oversight.

January: Wisconsin and Alabama GOP-drawn state legislative maps get thrown out, courts ask state legislatures to redraw

Alabama: A federal court found a dozen state legislative districts in Alabama were unconstitutionally racially gerrymandered. (The Democratic judge on that panel wrote that he would have thrown out 24 districts.) All 12 state legislative districts that were thrown out were represented by Democrats, 10 of them by African American legislators. The legislature is redrawing the maps now, and because there are so many, they'll likely have to redraw all state House and Senate districts.

Wisconsin: A  federal court ordered Wisconsin’s legislature to redraw state House legislative districts after finding in November that the districts were unconstitutionally partisan.

Partisan. That's the key. This marks the first time in a decade that a court has thrown out legislative maps because they favored voters of one party over another. And therefore, this will be the first time in a decade that lawmakers will have to redraw maps specifically to make them more fair for both parties (not just to consider race). The shake-up is so profound that the legislature will probably have to redraw the state Senate districts as well.

Wisconsin’s attorney general, a Republican, has appealed to the Supreme Court. If they take up the case, it could be monumental: The Supreme Court has never been clear on what, exactly, constitutes illegal partisan gerrymandering, so a ruling on Wisconsin could set precedent for years to come.