No - a portal only shows related records. You can, however, place your web viewer in the header or footer of a list/table view.
Why don't you create a second table occurrence in the table graph, based on the first table, then create a relationship between any of two fields and use "x" relationship ( and not the "=" ).
You'll then be able to create a portal, and the "x" simply means that 'all records' will be displayed, or related.
Thank you, this did exactly what I needed.