In case they're a useful reminder, here are some WaPo charts of contemporaneous polls on civil rights protests. https://www.washingtonpost.com/news/the-fix/wp/2016/04/19/black-lives-matters-and-americas-long-history-of-resisting-civil-rights-protesters/

60% of people polled had "unfavorable" feelings about the imminent March on Washington. John Lewis, then 23, would be its youngest speaker.

John Lewis was one of the 13 original Freedom Riders.

From a 1961 poll: "Do you approve of disapprove of what the 'Freedom Riders' are doing?"

22% approve, 61% disapprove, 18% no opinion

John Lewis was an organizer in the Nashville sit-in movement.

"Do you think 'sit-ins' at lunch counters, 'freedom buses' and other demonstrations by negroes will hurt or help the Negro's chances of being integrated in the South?"

28% help, 57% hurt, 16% no opinion

All that said, most people @pewresearch polled (67% overall) in June approved of Black Lives Matter protests. https://www.pewsocialtrends.org/2020/06/12/amid-protests-majorities-across-racial-and-ethnic-groups-express-support-for-the-black-lives-matter-movement/

The same week, Lewis said this of protests: “You must be able and prepared to give until you cannot give any more." https://www.washingtonpost.com/podcasts/cape-up/civil-rights-icon-john-lewis-is-deeply-moved-by-todays-demonstrations/

Fuller quote, from @CapehartJ interview:

"I asked him what he would say to people who feel as though they have already been giving it their all but nothing seems to change." https://www.washingtonpost.com/opinions/2020/06/10/john-lewis-black-lives-matter-protesters-give-until-you-cannot-give-any-more/

"'You must be able and prepared to give until you cannot give any more,' Lewis said. 'We must use our time and our space on this little planet [...] to make a lasting contribution, to leave it a little better than we found it, and now that need is greater than ever before.'”