if it is just light overspray then your best bet would be to get some 1200 grit wet/dry paper. Soak it in warm water and then gently rub at the over spray. This will lightly rub away the overspray leaving you with the clearcoat that was originaly on the wheel.
The area will now be matt (rather than glossy) due to the sanding so get some polish (tcut will do) and apply to the area you have just sanded. Polish up the area and wipe off the remaining residue from the polish.
Should look good as new.