Campaign Ids and impressions for a closing

SELECT   manifests.campaign_id,SUM(delivery_item_entries.impressions)
FROM     delivery_item_entries
  INNER JOIN delivery_items on delivery_item_entries.delivery_item_id = delivery_items.id
  INNER JOIN third_party_placements on delivery_items.third_party_placement_id = third_party_placements.id
  INNER JOIN ordered_placements on third_party_placements.ordered_placement_id = ordered_placements.id
  INNER JOIN placements on ordered_placements.id = placements.ordered_placement_id
  INNER JOIN plan_rows on placements.plan_row_id = plan_rows.id
  INNER JOIN plans on plan_rows.plan_id = plans.id
  INNER JOIN manifests on plans.manifest_id = manifests.id
WHERE    delivery_item_entries.closing_id = 1
GROUP BY manifests.campaign_id