One of the 13 original founding states of the United States, Pennsylvania came into being in 1681 as a result of a royal land grant to William Penn, the son of the state's namesake. It was the second state to ratify the United States Constitution, on December 12, 1787. Today, it is the 33rd-largest, the 6th-most populous, and the 9th-most densely populated of the 50 United States.
Pennsylvania is one of four U.S. states that calls itself a "Commonwealth." The term does not describe specific political status or legal relationship when used by a state; those that use it are equal to those that do not.
For most of the second half of the 20th century and into the 21st century, Pennsylvania has been a powerful swing state. It only supported the losing candidate in a presidential election twice from 1932 to 1988. Since 1992, Pennsylvania has been trending Democratic in Presidential elections, voting for Bill Clinton twice by large margins, and slightly closer in 2000 for Al Gore. A majority of Pennsylvanians voted for John F. Kerry over George W. Bush in 2004, and for Barack Obama over John McCain in 2008. In the 2016 presidential election Donald Trump became the first Republican candidate to win the state since 1988, 48.6% to 47.8%. The state holds 20 electoral votes.