Having worked at a farmer's market for 3 years, I can definitively say that local is better than organic. One of the farmers I work for has done a lot of research on the subject, and he won me over.
What most people don't realize is that organic doesn't mean "no pesticides;" it just means no synthetic pesticides. Organic chemicals can be just as toxic to humans, and to the environment. If they're not as effective as synthetic chemicals, some farmers use more of the organic than they would of the synthetic. & Of course, large farms that ship across the country or world are more likely to spray indiscriminately because it's more efficient monetarily. Whereas small farms that can't justify the cost of going completely organic often employ organic methods anyway. They use crop rotation, non-chemical obstacles to pests, and diversified heirloom seeds that foster natural immunity to pests. (Heirloom varieties are usually tastier, too.)
So considering the environmental impact of fossil fuels used to ship organic, but non-local food, as well as the economic benefits of supporting small, local businesses, it's clear: buying local over organic isn't just a preference. It's the right thing to do.