In a Facebook ad, Republican congressional candidate Joe Kent claimed "rampant voter fraud" in the 2020 election, a misinformation problem that Facebook has attempted to address.
The ad, which ran in mid-May as part of a campaign to win Washington state's third district by a former president Donald Trump-endorsed candidate, was one of dozens by the campaign that went undetected by Facebook's system.
That system was created to eliminate misleading claims that the election results were skewed. It's an example of the kind of misinformation that's already being tested on Facebook ahead of the midterm elections.
According to researchers, human rights advocates, and some former employees, Facebook should tighten its policies to prevent election-related misinformation from spreading.
The primaries are already well underway, and Trump urged at least one candidate to declare victory before the results were known on Wednesday.
Facebook, like many other social media platforms, is continually changing and updating policy as it learns how its platform has been abused, with the goal of resolving issues in time for the next election.