I saw a Magus build that started out doing 4d6 shocking grasp at 1st level, just cant remember the traits and feats it had, and I cant find the thread again.
A +1 caster level bump putting a shocking grasp at 2d6, delivered through a greatsword does 2d6 + 2d6 electricity, and that's pretty easy to get from a variety of sources.
I know gifted adept is the trait that lets you bump the CL of one chosen spell by +1. I don't know where the other +2 is from maybe some kind of elemental specialization?
The allied caster teamwork feat can provide another +1 caster level bonus...