score:3

Accepted answer
var results = from q in query
    group q by new {q.soldtocontactid,
                    firstname=q.contact.firstname,
                    lastname=q.contact.lastname} into g
    select new leadbuyersbystateitem {
        contactid = g.key.soldtocontactid,
        firstname = g.key.firstname,
        lastname = g.key.lastname,
        contactcount = g.count()
     };

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