As a nationwide drought threatens to drive up prices for food staples this fall, it could pose an even greater challenge for the one in five Americans who weren't able to afford food so far this year.

For the first six months of 2012, Gallup surveyed 1,000 Americans each day to see whether they'd been able to afford basic food. From the report:

"In 15 states, at least one in five Americans say they struggled to afford the food they needed at least once during the past 12 months. Nationwide, 18.2% of Americans so far in 2012 say there have been times when they could not afford the food they needed, on par with the 18.6% who had trouble affording food in 2011."

When broken down by states and regions, there were huge discrepancies in responses. From coast to coast, the Southern half of the nation struggled the most by far. Twenty-five percent of Mississippians reported struggling to afford food, the highest total in the country, while just 9.6 percent of North Dakota residents said the same.

And rough waters are still to come.

Within two months, prices for beef, pork, poultry, and dairy will begin to rise and the processed and packaged foods so many low-income families rely on for cheap meals will see prices soar within a year, according to the U.S. Department of Agriculture.

The map below depicts each state's rating on Gallup's Well-Being Index. The ranges relate to how many respondents reported being unable to afford food at least once.