(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).

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