Iowa may be a blue state politically, but when it comes to farm subsidies Iowa is all red (see pictures above and below, red dots indicate locations receiving farm subsidies). According to the Environmental Working Group Farm Subsidy database, 70% of Iowa farms received subsidies in 2002 (most recent year available, data here), the second highest percentage in the country (see chart above).
During the 2003-2005 period, Iowa led the nation by harvesting almost $4 billion in cash, i.e. farm subsidies (data here), or 10.8% of the $37 billion paid in total farm payments during that period. Iowa benefited from the generous $18 billion of subsidies given out by the U.S. government for growing (or not growing) corn, which is an amount equal to the subsidies paid for cotton, wheat, rice, soybeans, dairy, peanuts and barley COMBINED (data here).
Farm subsidies in Iowa are so popular and common that many citizens of the city of Des Moines partake of the government's generous agricultural largesse (see map below, red dots represent mailing addresses of "farmers" receiving subsidy payments).