In the past, Pandora used two factors to infer how a listener would vote: the listener’s zip code, and the voting habits of people in that zip code.

Now, according to Pandora spokesperson Heidi Browning, they will add data on listener music tastes. It may sound like shaky science, but researchers have seen a correlation between the types of artists a person listens to and how he or she votes. 

In 2012, Brian Whitman, the founder and CTO of The Echo Nest, a music intelligence platform, tracked what people listened to. Here are his findings.

Artists whose fans are most likely Republicans: 

1. Kenny Chesney
2. George Strait
3. Reba McEntire
4. Tim McGraw
5. Jason Aldean
6. Blake Shelton
7. Shania Twain
8. Kelly Clarkson 
9. Pink Floyd 
10. Elvis Presley

Artists whose fans are most likely Democrats:

1. Rihanna
2. Jay-Z
3. Madonna
4. Lady Gaga 
5. Katy Perry 
6. Snoop Dogg
7. Chris Brown
8. Usher
9. Eminem
10. Bob Marley

And then, there are artists that aren’t really predictors. They attract both Republicans and Democrats. Six of the ten, says Whitman, are metal bands:

1. The Beatles
2. Marilyn Manson
3. The Rolling Stones
4. Johnny Cash
5. Pantera
6. Alice in Chains
7. Paradise Lost
8. Moonspell
9. Fleetwood Mac
10. Tiamat 

Research from The Echo Nest