Fwiw, I was not impressed with the source I've seen most often quoted for, Chenoweth and Stephan's Why Civil Resistance Works. Their case was built primarily on a piece of very high level statistical analysis showing that the conflicts they deemed to have been nonviolent were more likely to have been successful in some way, without examining the causes or initial conditions of the conflict or if the success or failure. The analysis is ahistorical in at least the case of the US Civil Rights movement, which was many things and nonviolent only in some places, and likely in many of the others, too. While I wouldn't say their work is entirely without merit, I also would not use it as a guide for resistance strategy in any way.
I worry about this 3.5% number giving folks in the US false hope and convincing liberals that the situation is not as immediately dire as it is, and that they should push back against others using a diversity of tactics, or simply ignore the whole thing and hope it never touches them.