First recorded by The 5th Dimension (1967).
Hit version by The Brooklyn Bridge (US #3 1969).
Also recorded by Jimmy Webb (1996).
From the wiki: “‘The Worst That Could Happen’ was originally recorded by The 5th Dimension for their 1967 album of nearly all-Jimmy Webb-composed songs, The Magic Garden. The song depicts a man reflecting on an affair he’d had with a woman with whom he is still in love, but who is about to marry someone else. It has been stated that, along with ‘MacArthur Park’ and ‘By The Time I Get to Phoenix‘, ‘The Worst That Could Happen’ is about a relationship that Webb had had with a woman named Susan.
“Webb’s song was later recorded by Johnny Maestro & the Brooklyn Bridge and reached the Billboard Hot 100’s Top-40 in 1969.
“The song is noted for the quoting of Mendelssohn’s ‘Wedding March’ from the incidental music to ‘A Midsummer’s Night’s Dream’, which is heard at the song’s end, which in the Brooklyn Bridge version, is played by a handful of trumpets, while in the Fifth Dimension version, is played by an electric organ.
“Jimmy Webb recorded his own version of the song for his 1996 album Ten Easy Pieces.”