Iowa's state fair: Why presidential hopefuls go there

Iowa's state fair is a place that can make or break a presidential candidate.

At least, that's how tradition would have it.

Presidential candidates traditionally go there to meet the butter cow - a life-sized cow sculpted of wood, wire and salted butter.

They also address crowds, who pass comment on who they would like to lead the parties and become the next US president.

Iowa is one of the crucial states in the primaries to elect party candidates.

BBC news has asked fair goers who they favour this year.

Video journalist: Andrew Webb