[2] Democrats held a special convention during which State Representative Marty Flynn won the party's nomination.

[11] Following the death of Republican state representative Mike Reese, House Speaker Bryan Cutler announced that a special election for the 59th legislative district would take place on May 18 (in conjunction with the 2021 primary).

[14] Republicans held a special convention and nominated Leslie Rossi, a Latrobe native and creator of the "Trump House".

[19] House Speaker Bryan Cutler called for a special election for the 60th legislative district on May 18, in conjunction with the 2021 primary.

Judge Mary Hannah Leavitt, a Republican, declined to run for retention for an additional 10-year term.

[42] Had Judge Leavitt won retention, she would have only been eligible to serve for one year before her mandatory retirement by December 31, 2022.

[43][44] Governor Tom Wolf appointed Judge Drew Crompton[45] to fill the vacancy, who opted to run for reelection.

[46] A recount was triggered because Dumas and Crompton finished within half a percentage point of each other in the initial tally.

In 2020, Governor Tom Wolf declared a disaster emergency for the Commonwealth of Pennsylvania due to the COVID-19 pandemic.

Several Republicans, led by state representative Russ Diamond, opposed these public-health measures and introduced two amendments (2021-01 and 2021–02) to the Pennsylvania Constitution to restrict the emergency powers of the governor.