From the Document: "Most voters reported voting in person in 2018, but the onset of the COVID-19 [coronavirus disease 2019] pandemic has complicated in-person voting for certain subsequent elections in 2020. Health risks associated with close contact have prompted concerns about some of the standard interactions involved in preparing for and conducting in-person voting. States have taken various steps to address such concerns for some of their 2020 elections, including postponing election dates, offering curbside voting, and relocating polling places. One common response has been to expand 'mail voting', in which voters receive ballots by mail rather than in person. Expanding mail voting could help address health risks but may come with its own challenges. Whether or how mail voting should be expanded and what role, if any, Congress should play in this policy area have been subjects of debate in the 116th Congress."
CRS Insight, IN11356
Congressional Research Service: https://crsreports.congress.gov/