(CNN) On Thursday, the Supreme Court showed how much difference who wins the presidency makes.
Armed with a five to four conservative majority thanks to President Donald Trump's appointment of Neil Gorsuch and Brett Kavanaugh over the past two years, the Supreme Court said it had no role to play in partisan gerrymandering -- a decision that amounts to a massive political victory for Republicans, not just in the moment, but also likely for the next decade-plus.
While the court didn't give Republicans everything they wanted on Thursday -- rejecting the addition of a citizenship question to the census that the Trump administration had pushed for -- the ruling on line-drawing with political concerns as a primary motivation is an absolute game-changer for a party that has already reaped the considerable rewards of its ongoing domination at the state legislative level.
What SCOTUS said Thursday was, essentially, if state legislators want to draw the lines of their own districts and those of their members of Congress using political calculations, it's not the court's job to stop them. That state legislatures are given that power and can exert it as they see fit.
On its face, this ruling impacts both parties equally. After all, both parties have shown a willingness over the last several decades to push their partisan advantage in the decennial line-drawing process. And the cases on which the court ruled on Thursday involved one Democratic gerrymander (Maryland) and one Republican one (North Carolina).
But, to see things through that this-hurts-both-sides-equally frame is to miss the forest for the trees. Thanks to avalanche elections in their favor in 2010 and 2014, Republicans have an absolute stranglehold on the state governments.
According to the National Conference of State Legislatures, Republicans currently have full control over 30 of the 49 partisan legislatures in the country. (Nebraska has a unicameral legislature where members are elected on a nonpartisan basis.) In 22 states, Republicans not only control both chambers of the state legislature but also hold the governorship -- giving them total control over state government. (Democrats have total control in 14 states while control is divided between the parties in 13 states.)
While those raw numbers are startling, they don't even fully tell the story of why Thursday's gerrymandering ruling is such good political news for Republicans. The key fact? In most of the large population states where seats are expected to be gained or lost -- based on population increase or decrease over the last decade -- Republicans have total control, and large enough majorities that should insulate that control barring a massive Democratic landslide in 2020.
Take Texas, which is projected to gain three new congressional seats after the next census due to its off-the-charts population surge. Gov. Greg Abbott (R) was just reelected in 2018. In both the state House and state Senate, Republicans have comfortable majorities -- although those majorities were reduced somewhat by Democrats in the 2018 midterms. Which means that Republicans are going to be in charge of drawing what the congressional lines will be in the state through 2030 -- and now, thanks to the Supreme Court, have no concern of losing a constitutional challenge that they drew districts solely to leverage their political position.
Florida, which is expected to gain two more seats after the 2020 census, is a similar situation. Gov. Ron DeSantis (R) was elected in 2018. Republicans have a 23-17 seat edge in the state Senate and a 73-47 margin in the state House. Which means -- and stop me if you've heard this before -- that Republicans will have unfettered control of drawing a map that heavily advantages their party's political prospects not just in the 2022 election but all he way through the 2030 census.
Now, there's no question that Republicans -- thanks to the gains they made in 2010 -- have already drawn a bunch of maps that come close to maximizing their political edge. Put another way: They've already squeezed a lot of juice from the gerrymandering fruit, and it's not clear how much is left.
And there will likely be a renewed push -- in the wake of the court's ruling -- by Democrats and election reform types to pass laws that take the line-drawing out of the hands of state legislators and give that power to independent/bipartisan/nonpartisan commissions.
But, in order for those sorts of efforts to work, state legislatures have to willingly give up a huge bit of political power. And politicians -- of either party -- are not big on that sort of thing.
Make no mistake: The Supreme Court's ruling on partisan gerrymandering is a massive moment in electoral politics. It could very well help Republicans retake control of the US House as soon as 2022 and, if the party plays things smartly over the next two years, could well put them in position to hold that majority for much of the next decade.