Ted Cruz, counting on evangelicals, is in a tough Iowa homestretch | McClatchy Washington Bureau

The GOP presidential debate Thursday night left Sen. Ted Cruz a little the worse for wear as rivals questioned his positions and his character.

Once the front-runner in Iowa, Cruz is now running second to Donald Trump in polls and struggling to hold on as the campaign enters its last weekend before Monday’s first-in-the-nation caucuses. That means a barnstorming weekend that will see Cruz visit the last two of Iowa’s 99 counties that he hadn’t visited already – a feat that’s intended to show his commitment to the state.

Then the goal will be to get his supporters to Monday’s caucuses, concentrating on evangelicals, who in recent elections have made up more than half of caucus voters and who Cruz has said from the start are the key to victory.

For months his campaign has built up evangelical support, gaining endorsements from more than 150 faith-based leaders and creating expectations of a first-place finish. In many ways, that makes Cruz the Republican with the most at stake Monday night.

“Ted’s got a big hill to climb here. The expectation is for Cruz to win,” said Robert Brownell, a Republican supervisor for Polk County, which includes Des Moines. But Brownell, an evangelical who backs Sen. Marco Rubio of Florida, said a surprise is possible. “I don’t think Cruz has the market cornered,” he said.

Cruz’s game plan – win in Iowa, be competitive in New Hampshire and finish first in South Carolina – was intended to build momentum going into Super Tuesday, March 1, when many Southern states, including Cruz’s home state of Texas, hold primaries. But that plan is threatened by Trump’s January surge, which has put Cruz in second in many Iowa polls.

That position appeared even more precarious Friday after Trump’s refusal to be part of the Fox News debate put Cruz in the middle of the stage – and of his rival’s attacks.

“I didn’t think Cruz did all that well in the debate,” said Timothy Hagle, professor of political science at the University of Iowa, who added that he’s hearing Cruz support has slipped in the last week.

Still, Hagle said all was not lost for the Texas senator. “He seems to have the best ground game in Iowa, and that’s very important,” Hagle said. “If he’s slipping a bit, the ground game can help to minimize the damage.”

In the debate, Cruz had trouble explaining video clips that showed him supporting an amendment to an immigration bill in 2013 that would have given legal status, though not citizenship, to people who are in the U.S. illegally. He has denied that he wanted the bill to pass. His explanation: “The fact that each amendment didn’t fix every problem didn’t mean that I supported the rest of the bill.”

Cruz’s opposition to a federal mandate for ethanol had already provoked Iowa Gov. Terry Branstad to urge voters to defeat the Texan at the polls. Cruz’s answer to the ethanol issue in the debate – “I don’t believe Washington should be picking winners and losers” – seemed only to inflame the governor, who was in the debate audience.

Friday, Branstad stepped up his criticism of Cruz, saying he had a “poor performance” in the debate and didn’t understand the importance of the corn-based fuel to the state. “He was ahead on polls, but now he’s dropped below Trump,” he said at a taping of C-SPAN’s “Newsmakers.”

As for Trump, he was gleeful Friday about Cruz’s performance. “Boy, he got really pummeled last night. He got pummeled,” Trump said at a New Hampshire campaign event. “And they didn’t even mention that he was born in Canada.”

Trump has questioned Cruz’s eligibility to be president since the Constitution stipulates the person be a “natural born citizen” of the United States. While many constitutional scholars say Cruz’s mother being a citizen made him a citizen at birth, others have weighed in, saying he is not or that it is unsettled. There have already been several legal challenges.

“Now, Ted Cruz may not be a U.S. citizen. Right? But he’s an anchor baby in Canada,” said Trump.

Larry Sabato, director of the Center for Politics at the University of Virginia, credited Trump’s questioning of Cruz’s eligibility to serve as president for Cruz’s drop in the polls, even though Sabato called the issue of Cruz’s qualifications “nonsense.”

“But Trump’s gambit worked,” Sabato acknowledged. “In politics emotion often checkmates reason.”

And there is the lingering question around Cruz of how well he gets along with others, something that was on display during the debate. He got into a testy exchange with moderator Chris Wallace over whether he could respond to a question asked of New Jersey Gov. Chris Christie, and he complained later that all the questions had been set up to attack him.

“Without Trump there, Cruz became the piñata and he whines about it,” said Dennis Goldford, political science professor at Drake University. “The aggrieved saintly innocence act didn’t work.”