3. Diversity of voter structure Pennsylvania has a complex voter structure. Urban areas such as Philadelphia in the east and Pittsburgh in the west tend to support the Democratic Party, while rural areas in the middle tend to support the Republican Party. This diversity makes Pennsylvania's election situation unpredictable and increases its importance in the election. 4. Historical influence Since 1996, Pennsylvania has voted for the eventual winner in every presidential election, showing its key role in determining the outcome of the election.