According to The New York Post, the presidential candidates will spend the equivalent of $200 per vote in Iowa.
That's $50 million on the approximately 250,000 people who turn out for the caucuses. (Let that sink in a minute. The political fate of the country is in the hands of 250,000 people standing around in living rooms and bingo halls in Iowa. Now THAT's representative democracy!)
Says the Post: "The $50 million figure includes more than $30 million for TV ads, more than $1 million for radio ads, and more than $10 million for direct mail."