"In September 1970, Vice President Spiro T. Agnew, in a speech in Las Vegas, warned that drug use was threatening 'to sap our national strength'..."

"... and called out a number of pop songs, including the Beatles’ 'With a Little Help From My Friends' and the Byrds’ 'Eight Miles High,' as 'latent drug culture propaganda.' Within a year, under the Nixon administration, the Federal Communications Commission warned broadcasters about playing songs with lyrics that might promote drug use. As a result, 'One Toke Over the Line' was banned by radio stations in Buffalo, Miami, Houston, Washington, Chicago, Dallas and New York. Brewer & Shipley, Mr. Brewer said, came to embrace the crackdown as 'a badge of honor.'"

From "Michael Brewer, Whose 'One Toke' Was a Big Hit, Is Dead at 80/The duo Brewer & Shipley reached the Top 10 in 1970 with 'One Toke Over the Line,' a ditty about marijuana that ran afoul of Nixon-era censors" (NYT).

Brewer lived to be 80 and that was half a century after he expressed this conception of how he wanted to die: "My last wish will be just one thing/Be smilin' when I die/I wanna be one toke over the line, sweet Jesus/One toke over the line..."

The singer was "sitting downtown in a railway station" and "just waitin' for the train that goes home, sweet Mary." 

Even if the song originated from an exclamation about smoking marijuana, it seems that the substance of the song is religious. The metaphor of the train is seen in other songs, such as "People Get Ready (There's a train a-coming....") and "This Train (Is Bound for Glory)."

I wouldn't brush off "One Toke Over the Line" as a "ditty."

And by the way, screw Agnew. Back in 1970, young people easily opposed censorship. Who would have thought that in 50 years, the tables would be turned and the young would embrace it?