I need assistance; I’m stuck on a process to combine data within a single feature class (merge)
I need to merge - intersect geo-processing results within a single feature class
Example screen shot:

I used the geoprocessing: intersect tool to combine polygons (county and zip code) the intersect result created several polygons; now I need to merge by zip code choosing the largest polygon {not sure how to do that; except to manually select by shape_area}
* I want keep all of the attribute fields > I'm looking for a batch merge function*
After the merge is complete and there are no duplicate zip code numbers I need to dissolve by Senate districts.
Final product should be a Senate District feature class with number of constituents per district
Data to create the product is excel file, zip code poly, county poly and Senate district poly
Thank you for your expertise,
Jerry