According to the Inquirer, Costello has told GOP leaders he is uncertain if he will continue his re-election bid.
From the Inquirer.
Among those facing a difficult challenge is Rep. Ryan Costello, who represents a Chester County-based swing district that Trump lost and that moved left in the recent redistricting imposed by the state Supreme Court.
Costello has told GOP officials that he was uncertain if he would seek reelection, given the shifting map and brutal political environment, according to four Republican sources. Costello is still circulating petitions to campaign but has not definitively said if he will run, leaving Republican leaders worried about having to scramble to find a replacement if he bows out.
Costello’s new Congressional district would have voted for Hillary Clinton in the 2016 elecion by almost 10 points, based off our analysis of the new Congressional maps.