Hi Daisey,
 
I would talk to both the teacher and the principal about your concerns. However, they may be hesitant to switch classes for your daughter for the reason you've provided, because it may be that there will often or occasionally be someone in your child's class that you wish she wasn't around. Also, given that the two children are in the same grade and are neighbors, it may be that they'll play together during recess and lunch, and/or be together at school assemblies and events. Switching classes may not necessarily solve the issue, and there may be other opportunities for your child to observe behavior you don't approve for her.  
 
Rather than removing your child from the classroom, you might alternatively consider talking with the teacher about your observations of the neighbor child's behavior, and the behavior that you expect of your child. Ask the teacher to monitor the situation and keep you apprised of any issues that arise. You could also request that your daughter and the neighbor child be seated far from each other in class.
 
Consider also talking with your daughter about the behavior you expect of her at home and school, as well as about the consequences or what she can expect if she doesn't behave according to your and the school's rules. It isn't always entirely possible to keep our children completely shielded from behavior we don't like, and these situations can be learning opportunities, or opportunities for you to guide your child in the direction you'd like her to go.
 
I'm including below some resources to support you in your discussions with the teacher and principal, and for your decision-making and actions around peer influences. I hope your daughter has a wonderful school year.

Daisey,
I think this is a great opportunity for you to be proactive with your daughter.  Rather than changing teachers, you can talk to your daughter about your own expectations and behavior expectations.  As the parent above said, there will always be a child in the class that is not the easiest to handle.  If you do talk to the teacher, just mention your child.  Talk to the teacher about how you would like to know if behavior changes or if she sees changes.  Teachers will often not talk about other students, due to confidentiality laws.
 
Good Luck!