Depends on which state you are in. You can look up the voter registration deadline for your state online.
I'm in FL and mine is October 7, but since the SSN has to be updated after naturalization, with 7 months processing time currently, I have a feeling it's not happening for me.
IMO you don't need a lawyer, and even if things get complicated or you get an RFE, a little research and questions in the forums will be enough.