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During the course of Cruz's trip through the caucus state, GOP rivals like Donald Trump lobbed attacks on Cruz's citizenship and stance on biofuels like ethanol. Cruz revealed his discipline as candidate, sticking to engaging in retail politics and looking Iowans in the eye, all while doing his best to not to engage with "The Donald."
Here are five takeaways from the "Cruzin' to Caucus" bus tour.
1. The Question That Followed Cruz
Throughout 28 counties and over six days, one question repeatedly followed the Texas senator: where does he stand on ethanol. As Cruz finished his last stop in Waverly, Iowa, Saturday night, he started his walk backstage to leave and catch a flight to Texas. He was stopped by a voter with an urgent question about ethanol and the Renewable Fuel Standard.
"I would like him to have a good understanding of what it really means to the state of Iowa and the agricultural economy. There's a lot of jobs depending on the RFS and the ethanol industry. And I think it would bode well to his campaign to realize how important it is," said Jerry Calease, a farmer in Waverly, Iowa, who was the last person to ask Cruz about his ethanol stance during his bus tour.
Ethanol, made from corn, is a big deal in Iowa. The Renewable Fuel Standard requires a certain amount of biofuels like ethanol to be present in petroleum. Cruz says he opposes the federal mandate and wants to phase it out by 2022. He argues he wants no mandates or subsidies for any form of energy and his tax plan would eliminate them.
A deluge of ads, mailers and questions raised from rivals like Donald Trump have put Cruz, the frontrunner in Iowa, on the defense. An RV from a pro-ethanol group, America’s Renewable Future, trailed Cruz on the tour and handed out flyers calling him dangerous to farmers. Cruz called those claims "utter nonsense." In addition to addressing the issue at several of his campaign stops, Cruz published an OpEd in the Des Moines Register explaining his stance and was accompanied for half the trip by David Vander Griend, a man who supports Cruz and has built several ethanol plants in Iowa. He was also flanked by Rep. Steve King, a powerful conservative voice with Iowan farmers, who has endorsed Cruz.
2. The Question That Didn't Follow Cruz
While Trump and Sen. Rand Paul raised questions about whether Cruz's Canadian birth to an American mother disqualifies him from the White House, voters didn't press Cruz on the issue. Only once during the Q and A section of Cruz's campaign stops did Cruz give a full-throated defense of his citizenship.
In Mason City, a woman asked Cruz to clarify his citizenship.
He responded, "The law is straightforward on this."
"My mother was born in Wilmington, Delaware. She's a citizen by birth so I became an American citizen by virtue of being born to her. I have never breathed a breath of air on this planet when I was not a U.S. citizen. I was never naturalized. It was the process of being born that made me a US citizen," Cruz said.
3. Cruz Made Iowans Swoon (Literally)
Cruz visited several rural towns with populations in the thousands. One town had a population of 600. Despite the size of the towns and the snowy weather, Cruz turned out large crowds that fogged up windows at local restaurants and diners. Some took selfies with the senator. Others had him sign their copy of the Constitution. Some cried as they talked to Cruz and some literally swooned over him.
At his stop at a Pizza Ranch in Pocahontas, a woman fainted. In Strawberry Point, at Teluwut restaurant, another woman fainted. Each time, Cruz halted his speech and walked to check on the person. When it was clear they were OK, he'd return to the microphone and offer the same joke: his discussion of Hillary Clinton made them faint.
4. The New Things We Learned About Sen. Cruz
Cruz possesses the ability to give the same stump speech down to the word, using the same emotion and inflection in his voice with the crowd feeding off of it, often shouting an "Amen" or "Yes” as he speaks. Cruz also provides comedic relief, folding in impressions of JFK and quoting movies like "The Usual Suspects." When someone asked a question that got him excited, Cruz would quote "Jerry Maguire," saying, "You had me at hello."
The most revealing moments came from unexpected questions asked by voters. During the course of the bus tour, Cruz revealed he's a lousy golfer.
"Do I golf? Horribly," Cruz said in Waukon. "I do own clubs and I occasionally wack them into the ground and dig holes. But I think golf involves actually making contact with the ball and sending it in the direction of the hole and so by that definition, no, I don’t golf."
On the serious topic of the attack on the U.S. consulate in Benghazi, Libya, Cruz argued that Hillary Clinton deserved a political spanking for her role.
"We do know Hillary told her daughter Chelsea, well gosh, I knew it was a terrorist attack, while we were out telling the American people it wasn't. You know I'll tell you, in my house, if my daughter Catherine, the 5-year-old says something she knows to be false, she gets a spanking. Well, in America, the voters have a way of administering a spanking," Cruz said in Charles City.
5. Sometimes Even a Texan Has to Wear Snow Boots
A key part of Cruz's often worn campaign attire was missing: his cowboy boots. Cruz stuck to sensible snow shoes for Iowa’s snowy, icy terrain. Cruz replaced his beloved Lucchese cowboy boots with Ecco boots.