This week, the Pennsylvania Supreme Court released a new congressional map to replace the GOP-drawn map. Tuesday, Republicans announced that they'll sue to stop the map from taking effect for this year's midterms. The GOP currently holds 13 of the state's 18 seats.
Bottom line: There are 6 Pennsylvania districts held by Republicans that, under the new map, were carried by Hillary Clinton in 2016 or moved from being double-digit to single-digit Donald Trump territories. Additionally, there is one Democrat-held district carried by Trump.