The Supreme Court of Pennsylvania redrew the district in February 2018 after ruling the previous map unconstitutional.

In 2004 and 2006, Gerlach won re-election against fellow attorney and now Montgomery County Court of Common Pleas Judge Lois Murphy.

In the 2010 and 2012 elections, Gerlach defeated physician and Iraq War veteran Manan Trivedi, the Democratic nominee.

[6] In February 2018, following the Supreme Court of Pennsylvania's ordered redrawing of congressional districts, Costello announced he would not stand for reelection and retire at the end of the 115th Congress, leaving businessman Greg McCauley as the sole Republican candidate while the Democrats nominated Air Force veteran Chrissy Houlahan.

Its strange shape brought charges of gerrymandering by Democrats who argued it "looms like a dragon descending on Philadelphia from the west, splitting up towns and communities throughout Montgomery and Berks Counties.