Thomas Mifflin Democratic-Republican Thomas McKean Democratic-Republican The 1799 Pennsylvania gubernatorial election was between two candidates.

Incumbent governor Thomas Mifflin was not running.

Senator James Ross and Democratic-Republican Thomas McKean.

The retired Chief Justice of the Pennsylvania Supreme Court, McKean was a Federalist and a Mifflin ally, as both supported strong state executive power but rejected the domestic policies of the national government.

Some historians have pointed to McKean's victory as a forecast of Thomas Jefferson's election in the 1800 United States presidential election the next year.