John - I live in the USA and heard a version of this song sung while working in an Archeological site in the Mohawk River valley (Western NY), summer of 1983. We had a bunch of older grad students with ties to Science Fiction Fandom and it was one of them that sung it. Words were similar ut not quite the same. Before the verse about the congressman, there was a verse about socialism and disgruntled former members (I guess apostates but that's not what the lyric called them).

The one grad student, a geeky male, who sang it also was found of singing My Dead Dog Rover and other Dr. Demento material. The reaction wasn't outrage just a few chuckles from the guys and rolls of the eyes from the women. It was pretty much the kind of thing we expected from a guy who was never gonna get laid. It prolly didn't go over well because most of the students were in the Anthropology dept and didn't find mass suicde of new religious movements terribly amusing.