OSCEOLA, Iowa — Sen. Ted Cruz stood in a chilly barn Tuesday morning, invoking the Bible to encourage Iowans to judge candidates by their records.
"You should know them by their fruits," the Republican presidential hopeful said at the first of seven events across Iowa, just six days before the state's kingmaker caucuses.
But just as Cruz drew from the book of Matthew, news broke that Jerry Falwell Jr., a national evangelical leader and president of Liberty University, was throwing his support behind Cruz's key rival, Donald Trump.
It's a big blow to Cruz, the son of a preacher who announced his candidacy for president at Falwell's university last year. Cruz, who is banking on a big evangelical turnout at the caucuses to boost his candidacy, reminded voters here of his steadfast conservative views on social issues.
"If you want a president who will stand for life, for marriage, who will stand for religious liberty, ask who has a record standing for life, marriage, religious liberty," the Texas senator said.
While campaign officials declined to discuss the Falwell endorsement, they hinted at a "major" evangelical endorsement expected to come out on Tuesday night.
Cruz was also was scheduled to be joined by Iowa evangelical leader Bob Vander Plaats, who has already endorsed Cruz. Vanber Plaats told MSNBC that he "put principles over politics" in making his endorsement.
Vander Plaats said he hadn't been consulted about Falwell's decision to endorse Trump, but said he couldn't "ever get to a place where we could endorse Donald Trump."
"He talked about [his faith] at one of our events and said he doesn't have to ask God for forgiveness," Vander Plaats said of Trump. "The cornerstone of the Christian faith is knowing that you are a sinner."
Trump spent the morning criticizing Vander Plaats as a "phony" on Twitter, while the latter fought back with his own tweets.
Falwell's Trump endorsement was also a blow to Dr. Ben Carson, another evangelical candidate and a onetime front-runner in Iowa who has seen his poll numbers crash in the last few months. Carson has made his religious faith a key selling point on the campaign trail. A high-level Carson campaign staffer confirmed that the campaign had been speaking with Falwell about a possible endorsement, working on scheduling time for the evangelical preacher to join Carson in Iowa. Then, the staffer said, after Trump spoke at Liberty University, the line of communication dried up.
Falwell is the son of Jerry Falwell, Sr., the televangelist who founded the "Moral Majority," a group heavily credited with turning the religious right into a political force. The elder Falwell died in 2007.
This story originally appeared on MSNBC.com.