"Serial's" first season drew millions of listeners every episode, and the podcast's popularity may be spilling over to other shows.
The weekly show about the murder of a Maryland teen in the '90s is the podcasting world's first mega-hit. In fact, it's generated so much enthusiasm that one prominent podcaster says he's gaining more listeners as a result.
"The month before 'Serial,' I think we had about 5 million downloads. The month after 'Serial,' we've got 7 million downloads a month," said Stephen Dubner, host of "Freakonomics Radio."
Dubner said "Serial" likely brought new listeners as they visited the iTunes store and stumbled on other popular shows.
Related: Redditors raising $25k for 'Serial' podcast victim
According to podcast advertising company Podtrac, listeners have been rising steadily in the last 18 months -- the top podcasts have seen a 60% boost.
Growth was steady even before "Serial," but Podtrac CEO Mark McCrery said the show has generated a lot of enthusiasm, including two spin-offs that cracked the top 200 podcasts (Slate's "Serial Spoiler Special" and The AV Club's "The Serial Serial").
And if "Serial's" breakthrough was good for podcasters, it was even better for advertisers.
The MailChimp ads featured in "Serial" have become notorious. Stephen Colbert even asked "Serial" creator Sarah Koenig about the ads.
"To have Stephen Colbert ask about MailChimp in an interview with Sarah Koenig is incredible," said McCrery. "[The ad] became an unexpected hit and something that ingratiated everyone to the MailChimp brand."
