Today is a big confab in Iowa with a number of potential Republican candidates attending with the subject: agriculture.
As Politico describes it, the big issue is the renewable fuel standard (ethanol), which has long been shibboleth in Iowa. I vaguely remember some candidates (McCain?) getting credit from the chattering classes for refusing to support it. We'll see who takes what position and who has decided not to compete in the Iowa caucuses.
There's other issues, like immigration reform, which is big in agriculture but which isn't supported by most Republicans, and trade with Cuba, which Republicans also tend to oppose. All of which means that this first step on the road to the White House in 2016 may whet the appetite of followers of politics.