go over well with iowa voters, and cruz has had to explain his vote for that. donald trump last night went after him. here's more of what trump said. >> but with the ethanol, really, it's -- he's got to come a long way, because he's right now for the oil, but i understand it, oil pays him a lot of money, he's got to be for oil, right? the oil companies give him a lot of money, so -- but i'm with you. i'm with everybody. i'm with everybody. look, i'm self funding, i have no oil company, i have no special interests. >> this is a big issue, of course, to iowa voters. as you heard there, trump going over cruz's opposition to them in the past, something that is very popular with iowa voters, so trump really hoping that voters can hold on to that argument. of course, all of this critique comes at an interesting time, comes while cruz is making big gains in iowa, perhaps making