Brannan's voice is a tenor. Allmusic had reviewed his music and even compared him to female artists Ani DiFranco, Lisa Loeb, Sinéad O'Connor, and Liz Phair. Brannan's debut album "Goddamned" was described as lo-fi. Brannan's music was called "The Little Mermaid on crack". Brannan stated that he writes songs out of anger and pain. He has been compared to singer Rufus Wainwright by "The New York Times". Brannan also stated that he sees himself echoing the angry and sad sounds of female singers like Tracy Chapman and Joni Mitchell.