US midterms: Why are there so many guns in campaign ads?
US political campaigns have spent more than $6bn (£5.2bn) on adverts this year, a new record.
Republicans and Democrats have focused on very different issues and contrasting visions of America - but both have played on voters' fears.
Katty Kay decodes the two parties' election messages.
Produced by the BBC's Jason Armesto and Grace Conley.
