A special election was held in Pennsylvania's 8th congressional district on October 13, 1829 to fill two vacancies in Pennsylvania's congressional delegation before the first session of the 21st Congress. The vacancies had been caused by the resignations of Samuel D. Ingham (J) in March, 1829, and of George Wolf (J) on August 31, 1829, after being elected Governor of Pennsylvania
Election results
As the 8th district was a plural district with two seats, both empty, this election sent two people to Congress, bolded here for clarity.
Ihrie and Smith took their seats on December 7, 1829, the first day of the First Session of the 21st Congress
References
Pennsylvania's 8th congressional district special election, 1829 Wikipedia(Text) CC BY-SA