“We’ll do 90 minutes, Lincoln-Douglas, mano-a-mano, Donald and me,” Cruz said. “He can lay out his vision for this country, and I can lay out my vision for this country in front of the men and women of Iowa.”

Cruz, who has shied away from non-issue attacks on Trump, suggested Trump’s “hair might stand on end” if Kelly “asked him mean questions.”

The Texas senator also questioned why Trump would be “afraid” to debate him head-to-head.

“He’s been saying this past week he thinks I’m stupid,” Cruz slyly said on conservative Mark Levin’s radio program also on Tuesday night. “He should do very well with someone who is so stupid — away from moderators he’s so afraid of.”