Michael Brewer, half of the folk-rock duo Brewer & Shipley, who scored an unlikely Top 10 hit in 1970 with “One Toke Over the Line” — one of the most overt pop odes to marijuana of the hippie era and presumably the only one to be performed on the squeaky-clean “Lawrence Welk Show” — died on Tuesday at his home near Branson, Mo. He was 80.

His death was confirmed in a social media post by his longtime recording and performing partner, Tom Shipley. No cause was given.

While often categorized as a one-hit wonder, Brewer & Shipley actually notched two other singles on the Billboard Hot 100: “Tarkio Road,” which climbed to No. 55 in June 1970, and “Shake Off the Demon,” which sneaked in at No. 98 in February 1972.

The duo, who recorded many albums in the 1970s and a few more in the ’90s, were known for their songs’ socially conscious lyrics on topics like the Vietnam War. But it was their sunny signature tune, with its indelible line “One toke over the line, sweet Jesus,” that etched them into pop-culture history.

At the outset, Mr. Brewer and Mr. Shipley considered the song anything but a potentially career-defining composition. “We wrote it literally entertaining ourselves and to make our friends laugh,” Mr. Brewer recalled in a 2022 interview on the music podcast “A Breath of Fresh Air.”