But the singer/songwriter, who's since sold more than 30 million albums and written 13 No. 1 hits and 37 Top 30 chart hits, didn't stop there.
He went on to produce songs for some of the biggest artists in the music business, including 'N Sync, Luther Vandross, Barbara Streisand, Josh Groban, Vince Gill, 98°, Kenny Rogers, Sarah Brightman and Sister Hazel.
Teaming up with the late Vandross to write "Dance With My Father" was a huge success, not to mention a touching tear-jerker; it won a Grammy for Song of the Year.
Marx, who makes wearing your heart on your sleeve seem cool, has been continuously immersed in the contemporary music scene.
More recently, he's written and produced records for Daughtry, Leann Rimes, Katherine Jenkins, Travis Tritt, Emerson Drive, Natalie Cole, Keith Urban, Paulina Rubio, Kenny Loggins, Chris Botti, Michael Bolton, and actor Hugh Jackman.
His most recent release, "Emotional Remains," is his first solo recording in three years, and he calls it his most personal album yet. The album, produced by Marx, features collaborations with Matt Scannell, Jennifer Hanson and Kenny Loggins.
Marx stopped by "The Early Show Saturday Edition"'s "Second Cup Cafe" to perform his new song, "Over My Head" and his 1987 hit, "Should've Known Better."
Marx holds several records.
From 1987 to 1990, he became the first male solo artist in history to have his first seven singles reach the Top 5 on Billboard's singles chart, including the No. 1 hits "Hold Onto the Nights," "Satisfied," and the worldwide classic, "Right Here Waiting."
To this day, that feat remains unchallenged.