The Supreme Court announced this morning that it has agreed to take up an important gerrymandering case on appeal from the Western District of Wisconsin. Democratic plaintiffs are trying to challenge the constitutionality of partisan redistricting, and they found a sympathetic ear in a lower court.

The bottom line in this case is that Democrats are upset that they lost control of Wisconsin’s state government in 2010. They are now suing under the alleged right to have one’s districts drawn around oneself in a particular way based on one’s membership in (or one’s affiliation with, or one’s habit of voting for) a particular political party.