The reposts and expressions of shock from public figures followed quickly after a user on the social platform X who uses a pseudonym claimed that a government website had revealed “skyrocketing” rates of voters registering without a photo ID in three states this year — two of them crucial to the presidential contest.

“Extremely concerning,” X owner Elon Musk replied twice to the post this past week.

“Are migrants registering to vote using SSN?” Georgia Rep. Marjorie Taylor Greene, an ally of former President Donald Trump, asked on Instagram, using the acronym for Social Security number.

Trump himself posted to his own social platform within hours to ask, “Who are all those voters registering without a Photo ID in Texas, Pennsylvania, and Arizona??? What is going on???”

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Yet by the time they tried to correct the record, the false claim had spread widely. In three days, the pseudonymous user’s claim amassed more than 63 million views on X, according to the platform’s metrics. A thorough explanation from Richer attracted a fraction of that, reaching 2.4 million users.

The incident sheds light on how social media accounts that shield the identities of the people or groups behind them through clever slogans and cartoon avatars have come to dominate right-wing political discussion online even as they spread false information.