I have many followers in my group and was wondering if having so many affected the experience my main character receives.
Yes, it will... because you get individual experience (for your PC only) for every swing that hit. More followers, less hit made by you, and less experience. Also that's why a melee type PC will gain experience much faster than others. The experience from killing a creature is for the whole party (IIRC it is not shared (i.e. it's not "x pts of exp divided by number of party members" but x pts of exp for everybody))
SlytheTyrasit as kcwong said you gain experience for every hit you made, so having a lot of followers will somehow affect your character experience coz ur follower would surely get some hits that you would like. BTW, your followers level-up when u do, so, if you want, you may halt them from hitting the enemy, so you can hit them yourself..:wink: