Money has come in so fast and so unexpectedly that some groups even began to turn away and redirect donors elsewhere. Others said they still could not yet account for how much had arrived. A deluge of online donations has washed over organizations big and small — from legacy civil rights groups to self-declared abolitionists seeking to defund the police.

Black leaders and activists said it was a landmark moment in which a multiracial coalition protesting systemic racism and police brutality not only marched together, showed solidarity on social media and drove books about racism up the best-seller charts but also opened their wallets — especially during a pandemic that has driven 40 million people from their jobs and created one of the sharpest economic downturns in American history.

“To see millions of people give millions of dollars creates hope out of this moment,” said Glynda C. Carr, the president of Higher Heights, a group dedicated to building the political power of black women and which saw a spike of 15,000 donations in two weeks — about 10 times more than usual. “In the end, not everybody went out and protested,” she said. “This was a way to participate.”