I found this survey, by Public Policy Polling, to be pretty wonderful. PPP had one of the better records in the 2012 election season, which gives them some level of authority on public opinion polling. Basically, they polled 571 people on their music tastes, and used political affiliation as a crosstab. Bieber and Chris Brown were the two who saw the most agreement between the supporters of the two political parties. Since Chris Brown is actually a felon, that's a good reference point to where we're starting.
The most polarizing figures, Beyonce, Jay-Z, and Rihanna, all had positive ratings by Democrats and negative ones by Republicans. More research is forthcoming by the humble proprietor of this establishment to try to find out what these three artists have in common.