Several weeks ago as Michael Franti was notching his first Billboard Hot 100 single in a two-decade-plus career, he found himself in surgery with a ruptured appendix.

"The doctor is saying, 'It's a lot more serious than we expected but we'll do our best to get all the infection,' " Franti recalls from the New York set of Jimmy Fallon's late-night TV show. "And I'm thinking, 'Great, I have a hit song after all these years and I'll never hear it on the radio.' "

Thankfully, Franti survived. And he's not only hearing his feel-good anthem "Say Hey (I Love You)" on the radio, he's watching it climb several charts. This week the single moves 43-25 on the Hot 100, 16-14 on Adult Top 40 and 29-22 on Mainstream Top 40. Registering 54,000 downloads this week for a Nielsen SoundScan total of 417,000, the single jumps 28-17 on Hot Digital Songs. Its video numbers 1.3 million views on YouTube.

"Say Hey" -- a mix of dancehall reggae, folk and New Orleans zydeco -- appears on Michael Franti & Spearhead's current Anti- album, "All Rebel Rockers" (2008). In August, Universal Republic Records entered an agreement to promote and distribute the project after the song began taking off at triple A radio in the spring.

"[Anti- owner] Brett Gurewitz and his staff did a superior job in getting the song launched," Universal Republic president/CEO Monte Lipman says. "This strategic alliance just adds more people and resources to the mix. Michael is an exceptional artist and this song is my favorite kind of record: one you can't categorize other than using the word 'hit.' "

The single's success is a huge surprise for musician/activist Franti and Spearhead after 15 years of pioneering social humanitarianism through an intriguing fusion of genres, including hip-hop, funk, soul, reggae and folk. This time, though, Franti wanted to do something different.

"I've made political music my whole life," he says. "But at the end of this project, I thought we needed a fun, singalong song given the serious things happening in the world. And while I can't wipe the smile off my face about the song's success, it's just another reminder for me to just make music for the love of it."