Encouraging political news on ethanol and immigration.

he candidates are off and running in New Hampshire, but before the shouting gets loud again it’s worth sorting through the voter and turnout data from Monday’s Iowa caucuses for some early election-year lessons. There’s some good news for pro-growth Republicans. Start with King Ethanol, whose throne looks wobbly after Ted Cruz became the first Republican in recent memory to win the caucuses while refusing to bow down before the Iowa ethanol lobby. Corn is Iowa’s leading crop, and some 47% goes to make ethanol. But this is an industry that exists largely because Washington decrees that the nation’s gasoline include an increasing amount of the biofuel. Republican philosophy rejects mandates and subsidies, but every presidential year this principle runs up against ethanol and the Iowa caucuses. Most Republicans surrender.

That’s the path Donald Trump chose, but Mr. Cruz said he opposes all energy subsidies and mandates, including ethanol. He also argued that a free market would be better for Iowa farmers. For this brazen disrespect he was attacked by Iowa Gov. Terry Branstad, who called on Iowa Republicans to defeat Mr. Cruz because he is the “biggest opponent of renewable fuels” and whose son is state director of a pro-ethanol group. That’s a powerful lobby, but Mr. Cruz prevailed.

We have our differences with Mr. Cruz. But by taking the political risk of opposing ethanol mandates, he has liberated future Republican candidates from feeling they must first genuflect before corporate welfare that even Al Gore now admits was a mistake.

*** Then there’s immigration, which we have been told by countless voices on the right is the driving force behind populist anger against “the establishment,” whatever that is. But according to the Iowa entrance polls, the anti-immigration rage is overrated. Pollsters asked voters entering the caucus sites to select the issue that was most important to them, offering four choices in the GOP contest: immigration, the economy and jobs, terrorism, and government spending. Only 13% of voters chose immigration as most important, well behind the other three. Government spending was number one at 32%, the economy was second (27%) and terrorism third (25%). Among the immigration-first voters, Donald Trump (44%) and Ted Cruz (34%) did best while Marco Rubio won only 10%, well below his totals among voters who cared more about the other three issues. This isn’t surprising given the priority that Messrs. Trump and Cruz put on closing the U.S. borders and deporting illegals in the U.S. In politics you are what you emphasize. But immigration clearly wasn’t the killer app in Iowa that Mr. Cruz hoped it would be against Mr. Rubio.

Conservative Iowa is supposed to be the red-hot center of anti-immigration politics led by Rep. Steve King, who backed Mr. Cruz. But even in the Hawkeye State immigration doesn’t appear to be the presidential litmus test for Republican voters that some on the right have tried to make it. GOP voters are smart enough to know that reviving economic growth and preventing terrorism are higher priorities. The immigration debate isn’t over this year, and on Tuesday in New Hampshire Mr. Cruz launched another assault on Mr. Rubio. But the Iowa results suggest that the Floridian can neutralize the attack if he isn’t defensive and fights back. He’d be that much better positioned for the general election if he does.

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