"A majority of US adults (55 percent) now express at least some support for the movement, down from 67 percent in June amid nationwide demonstrations sparked by the death of African-American George Floyd in Minneapolis", Pew said in a statement accompanying the poll on Wednesday.
The percentage of Americans who said they strongly supported the BLM movement has dropped to 29 percent, a decline of almost one quarter from the 38 percent rating three months ago, the organization noted.
"In June, a majority of White adults (60 percent) said they supported the movement at least somewhat; now, fewer than half (45 percent) express at least some support. The share of Hispanic adults who support the movement has decreased 11 percentage points, from 77 percent in June to 66 percent today", Pew said.
The data was collected as part of larger surveys conducted 4-10 June among 9,654 US adults and from 8 September to 13 September among 10,093 adults, Pew said.
The black Lives Matter movement was created after protests that were sparked by the 25 May death of George Floyd, who suffocated as Minneapolis police officer Derek Chauvin knelt on his neck after he was arrested for trying to pass a counterfeit banknote.