State Senators have rebuffed part of a bill the Iowa Corn Growers Association touted as a compromise to boost ethanol use. The Senate voted down a proposal to require ethanol be offered by all Iowa gas stations at the lowest octane. Senator Jeff Angelo, a republican from Creston, said farmers were trying to dictate how gas station owners run their businesses. He says being asked to pick winners and losers among the state’s industries is a poor way to move forward.The Senate may take up the bill again as soon as today. As amended by Senator Angelo, the bill would force all Iowa gas stations to merely offer ethanol, at whichever price or octane a station owner wishes.