Bonnie Raitt actually fits into both categories. For the first fifteen years of her career, she was an under-appreciated artist who then had a late career renaissance. Raitt released 9 albums between 1971 and 1986 with some commercial success, but she did not have a top 40 single or a top 20 album. However, her bluesy sound and slide guitar made her a trailblazer and a critical darling.
Everything changed when Raitt released Nick of Time in 1989. Her 10th album was produced by Don Was (previously featured on the blog in Was Not Was) and contained the song that really broke her career wide open -- her cover of John Hiatt's "Thing Called Love." (Hiatt's "Slow Turning" was posted on ERV in March 2012.) The stars aligned and Raitt had a #1 album, one that would go on to sell some 5 million units in the U.S. Incredibly, "Thing Called Love" did not break the top 100 on the U.S. charts, but Raitt had multiple charting singles after it, including 5 top 40 songs.
The video of "Thing Called Love" features Dennis Quaid, (a friend of Raitts') who is basically there to flirt with her. In subsequent interviews, Raitt recounts that she was somewhat uncomfortable shooting videos, and thought that having an actor friend there would help the process.
And of course, the rougher but still excellent John Hiatt original: