In Iowa, presidential Republican candidates Donald Trump and Senator Ted Cruz are leading the polls, but the two are running close. One heated area of debate: renewable fuels. With Iowa the leading state for all things biofuels, voters want a president who will continue to support clean, renewable energy and rural economic development, something Trump as been a supporter and recently called Ted Cruz out for not visiting an ethanol plant. He’s not the only one on his case – America’s Renewable Future (ARF) has launched several campaigns against Cruz for his wishy-washy ethanol policy. Yet, this month, at an event in Cedar Rapids, Iowa, Cruz called for the end of all energy subsidies and stated, that as president he would “take on the EPA’s blend wall that is preventing ethanol and biofuels from having a larger share of the marketplace.”

This week, ARF has launched another attack on Cruz calling him a “career politician” and “doing the oil industry’s dirty work”. ARF State Director Eric Branstad, in reaction to his ethanol remarks in Cedar Rapids, noted that they want Iowans to know that, “unlike what Ted Cruz would like them to believe, he is a typical politician who will say one thing in Iowa and do another thing in Washington.”

The ad campaign focuses on his ties to Big Oil. Cruz’s campaign says he is against oil subsidies, but he told an Iowan that subsidies for the oil industry don’t exist and another that tax breaks exclusive to the oil industry, like intangible drilling costs, are not subsidies. In the Senate, says ARF, Cruz has introduced three bills to repeal the Renewable Fuel Standard (RFS) and has consistently voted against measures that would close tax loopholes for the oil industry. The only loopholes he has supported getting rid of are “enhanced oil recovery credits for producing oil and gas from marginal wells”—in the Energy Freedom and Economic Prosperity Act of 2014—which are inconsequential since taxpayers would see no revenue effect from them according to the Joint Committee on Taxation.

“Meanwhile Cruz has failed to introduce a single bill to repeal the $4.8 billion in subsidies that the oil industry receives annually,” said Branstad, “What’s worse is that he opposes the RFS because he claims it is a subsidy. But in fact, ethanol hasn’t received subsidies since 2011.”

Branstad added, “His entire career he’s been in the pocket of the oil industry and he will continue to stand up for it against Iowa farmers and the Renewable Fuel Standard.”