From 2003 to 2013 the district included suburbs of
Pittsburgh as well as
Beaver County,
Lawrence County, and
Mercer County. The district had a slight
Democratic registration edge, although it had voted for Republicans in several federal elections over the 2000s decade, including for President
George W. Bush in 2000 and 2004, as well as
Lynn Swann for governor in 2006. The heart of the district was a string of mostly white and middle class suburbs.
Plum and
Murrysville, two large and mainly residential boroughs, are the main towns in the suburban portion of the district that lies to the east of the city. Also included were the many suburban areas that make up northern
Allegheny County and southern
Butler County, Pennsylvania, including the larger communities of
McCandless and
Franklin Park, as well as several exclusive suburbs that have long been home to Pittsburgh's old money elite, including
Fox Chapel and
Sewickley. The northern suburbs had a generally moderate voting populace, which trends Democratic but makes up the swing vote, especially in races for national office. Further north, the district took on a different character. The suburban areas of
Beaver County are somewhat less affluent and were heavily labor Democratic. The areas of
Lawrence County and
Mercer County had a more rural feel, but also had a union Democrat center within the city of
New Castle. This district changed drastically when Pennsylvania's new districts went into effect on January 3, 2013. Due to slower population growth than the nation as a whole, Pennsylvania lost a seat in Congress in reapportionment following the
2010 United States census, and this seat was effectively eliminated. Most of the 4th district was merged into a redrawn
12th district, and the previous
19th district was rebranded as the 4th. Thus from 2013 to 2018, the 4th district was located in south-central Pennsylvania and included all of
Adams and
York counties, as well as parts of
Cumberland and
Dauphin counties. During this time, the district was represented by Republican
Scott Perry. The
Supreme Court of Pennsylvania redrew the state's congressional districts in February 2018 after ruling the previous map unconstitutional due to
gerrymandering. The fourth district was reconfigured as a Democratic-leaning area to the northwest of
Philadelphia for the 2018 election and representation thereafter. Geographically, it is the successor to the old
13th district, which was represented at the time by Democrat
Brendan Boyle. Boyle, however, opted to run in the neighboring
2nd district, the geographic successor to the
1st district, represented by retiring incumbent
Bob Brady. The bulk of Perry's representation, including
York and
Harrisburg, became part of a redrawn
10th district.
Gettysburg and Adams County joined a new, heavily Republican 13th district, which was the successor to the old
9th district of retiring Congressman
Bill Shuster. Areas to the south and east of York joined
Lancaster in a redrawn, heavily Republican
11th district, the successor of Republican
Lloyd Smucker's
16th district. == Counties and municipalities ==