While still in the original Broadway cast of “Hair,” Robin McNamara was only 23 when he hooked up with producer Jeff Barry (Monkees, Neil Diamond, Archies) and scored a million-selling bubblegum hit with “Lay a Little Lovin’ On Me” in 1970.

He may have been a one-hit wonder, and one of his ex-wives may have his gold record stashed away someplace, but McNamara hasn’t stopped living life.

Now based in Gulfport, Fla., the 47-year-old McNamara has been mailing out copies of a three-song demo tape to major labels in hopes of at least selling one of his songs to an artist who might consider doing a version.

“Honestly, ‘Lay a Little Lovin’ On Me’ was a wonderful time for me and a wonderful lemonade song,” he says, “but wasn’t the ’70s sort of a blur for everybody? I went through a couple of marriages and a couple of sad airplane rides, but now is now and you keep pursuing life.”

“Lay a Little Lovin’ On Me” peaked at No. 11 on Billboard’s singles chart. Though a second hit never followed, McNamara continued to tour in the ’70s with his backup band, later known as Exile (who themselves had a No. 1 in 1978 with “Kiss You All Over” and became a top country act in the ’80s).

He also appeared in the 25th anniversary revival of “Hair” and is considering the lead role of Jesus in a remake of “Godspell” this spring.

How does he see his chances this time around with the demo tape?

“Nil to slim to none, probably,” he says, with a laugh. “I do this because it’s like a passion for a craft. If you’re a carpenter, and you love to work with wood, then you love to work with wood and you create things and you hope people enjoy it. That’s what I do.”