Steven Rosenfeld had this very insightful study that investigates in what ways online propagandists attacked the 2020 election. Here is an excerpt of the study published in National Memo:

Partisan disinformation to undermine 2020’s presidential election shadowed every step of the voting process last year but took an unprecedented turn when the earliest false claims morphed into intricate conspiracies as Election Day passed and President Trump worked to subvert the results, according to two of the nation’s top experts tracking the election propaganda.

At the general election’s outset, as states wrapped up their primaries and urged voters to use mailed-out ballots in response to the pandemic, false claims began surfacing online—in tweets, social media posts, text messages, reports on websites, videos and memes—targeting the stage in the electoral process that was before voters. These attacks on the nuts and bolts of voting, from registration to the steps to obtain and cast a ballot, began as “claims of hacking and voter fraud… [that] honed [in] on specific events,” said Matt Masterson, who helped lead the Department of Homeland Security’s election security team.

“This is a lot of what we talked about with you at CISA [the U.S. Cybersecurity and Infrastructure Security Agency] in the lead-up [to Election Day], anticipating that were there were problems experienced, and then in the contested elections, those would be used to blow out of proportion or lie about what was actually taking place,” Masterson said, speaking to the nation’s state election directors in early February at a winter 2021 conference.

Read the full study here.