Las Vegas(CNN) Donald Trump on Thursday ripped Texas Sen. Cruz as a strident and unlikeable figure lacking the skills to negotiate and lead on behalf of the United States, soon after a new CNN/ORC poll showed the real-estate magnate with a commanding lead in Iowa.
Speaking to an enthusiastic crowd at a casino here in his first of two events of the day, Trump sought to neutralize the Texas Republican's most recent line of attack that he is part of the establishment. He charged that Cruz's campaign is rapidly losing support as his credentials as a negotiator come under fire.
"He had his moment and he blew it," Trump said after a reading a series of polls showing him surging in states around the country.
"He looks like a nervous wreck," he added. "He's going down."
Trump outlined a fiery critique against the Texas senator, noting that he has not been endorsed by any of his colleagues in the Senate. He went so far as to question Cruz's ability to relate to people.
"I heard he was a great debater, but I beat him in the last debate," Trump said. "He can debate, but he can't talk."
Dismissing Cruz's recent attack that he is the favored candidate of the establishment, Trump said, "We've got to be a little establishment. We've got to get things done. We've got to get along with people."
Trump also credited Sarah Palin, who endorsed him earlier this week, for Cruz's political success.
"If it weren't for Sarah Palin, he would not be a senator, just so you understand. He was at 2% and then she came on and he did fine," Trump said.
Cruz wasn't Trump's only target, as he called former Florida Gov. Jeb Bush a "lost soul" and mocking the lavish spending by the political committee supporting him given how little momentum they have produced for his campaign.
"Poor Jeb. He's doing another commercial on me. This guy, he's a maniac," Trump said as he opened his remarks. "He's not even on the scale -- these people, we've got a bunch of real dummies, I tell ya."
Trump added, "Jeb is down the toilet and Ted is starting to go down." He assured the crowd that if Bush halted his attacks on Trump, he would leave him alone.