tried google groups -- can I do groups with searchlogic and if so, how?

[timfong888]

I have the following using searchlogic:

@todos = Todo.contact_user_id_is(current_user).
          contact_campaign_id_is(@campaign).
          current_date_lte(Date.today).
          done_date_null.
          ascend_by_current_date

I only want @todos to contain a Todo record for a single contact_id (contact_id is an attribute on Todo).

Question: how can I group so that I there is only one record per contact_id in the @todos array?