Pennsylvania made history on Tuesday night when voters elected Democrats for all three state Supreme Court positions that were up for grabs, giving Dems the majority.

The Washington Post called such results one of the biggest court shake-ups in recent history.

Among the host of high-profile issues the court will decide on is redistricting. As Phillymag.com points out, the court plays a major role in deciding where district lines are drawn for state House and Senate seats. Those legislators in turn decide on congressional districting:

The party that controls the Supreme Court gets to appoint the chair of the states five member redistricting commission . The courts vote is tie-breaking, as the other commission members are comprised of two Democrats and two Republicans . Thats a big deal.

The State Supreme Court is also the final word on redistricting maps. Pennsylvanians who take issue with the redistricting commissions decision can sue, and the Court gets to hear and rule on those appeals.

Republicans control both chambers of the Pennsylvania General Assembly, as well as 13 of the states 18 congressional seats, even though the state otherwise leans Democratic. Tuesday nights results could change that. Depending on where the lines are drawn, Democrats could take back the majority of U.S. congressional seats in next years elections.