It began with a group of black women on a Zoom call who hit a million-dollar fundraising target in about three hours.
A series of similar Zooms have followed, targeting other groups on behalf of the Kamala Harris presidential campaign.
The latest on Monday night was a three-hour call titled "White Dudes for Harris", which organisers say attracted 190,000 people and raised more than $4m (£3.1m) in donations.
High-profile celebrities and politicians were among those present.
The US vice-president's bid for the top job is barely more than a week old. Still, it is harnessing a grassroots energy that did not exist for President Joe Biden, with supporters using modern video conferencing to reach motivated voters and fundraise virtually.
In the past week - roughly 100 days from Election Day - the campaign has raised $200m (£155m) and signed up more than 170,000 new volunteers.
And unlike big donors who helped persuade Mr Biden to step aside and end his run just days ago, it is hundreds of thousands of ordinary Democrats now generating "Kamalamentum".
Call attendance began in the tens of thousands - already a feat given Zoom meetings are usually restricted to 1,000 participants. But since then, two calls have drawn more than 150,000 people. Zoom did not respond to requests for comment on this story.
Republicans have criticised some of the identity-based virtual gatherings as "racist" and "desperate" pandering to liberal voters.
But while some may cringe at such overt use of identity to campaign, the impact of these virtual events is being taken seriously.
The Zoom sessions are "a signal that there is enormous enthusiasm out there for her candidacy," said Republican consultant and pollster Whit Ayres.
And, he said, it would be a mistake for Republicans to criticise the identity-based sessions.
“It backfires when you start attacking people because of their identity. Because everyone else who shares their identity feels like you're attacking them.''
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