Received a post card in the mail saying they have a parcel for us. Asking for us to call this number and ask for Pat Johnson. If they have a parcel for us then obviously they have our address so they can just mail it to us. Smells like SPAM to me.

The "package" is some cheesy "free gift".  It has to be delivered in person because the person bringing it is a salesman who will want to "test" your water.  Of course you will "need" some overpriced water filtration system.  They get around the DNC by having you call them and ask questions, then they can say you asked for information and they will simply be returning the call.
Take the post card to the post office and have them forward it to the postal inspectors.