The signatories represent both major parties and 36 of the 50 states, as well as the District of Columbia, Guam and Puerto Rico. Mr. Baxley, 76, who called the statement “one of the most touching gestures that anybody’s ever made on my behalf,” said that was the most meaningful part.

“When you look down that list, there’s many fine Republicans as well as Democrats,” he said. “And that’s the way it ought to be on issues like this, condemning sheer hatred.”

Though the decision not to address the statement to anyone in particular was deliberate — “We’re not trying to lobby anybody,” Mr. Tierney said — the context is clear. It has been less than two weeks since a man drove a car into a crowd of counterprotesters at a rally of white supremacists and neo-Nazis in Charlottesville, Va., and one week since Mr. Trump doubled down on his assertion that “both sides” were responsible. Much of the national conversation since then has focused on Mr. Trump’s refusal to do exactly what the statement urges: unequivocally condemn hate and those who espouse it.

“I had no absolutely no patience for them, or for public officials that didn’t stand up to them,” Mr. Baxley said of the K.K.K. A majority of Southerners also opposed the K.K.K. in the 1970s, he recalled, “but yet they didn’t speak up.”

Mr. Baxley, who now works at a law firm in Alabama, was not involved in writing Monday’s statement but said he agreed with its message.

“Anybody that espouses that rhetoric and that doctrine is not just expressing a difference of opinion — they’re advocating the most horrific acts that you can imagine towards innocent people,” he said. “It just cannot be tolerated in a just society, or else you get something like you had in Nazi Germany. You just can’t allow that to take root.”