Donald Trump Calls Ted Cruz A 'Maniac,' Cruz Hits Right Back

As Ted Cruz challenges Donald Trump in the polls, the billionaire is going on the offensive.

Read: Here's Jon Stewart Performing His Best Donald Trump Impression

"When you look at the way he's dealt with the Senate, where he goes in there, like a, you know, frankly like a little bit of a maniac, you're never going to get things done that way," Trump said to Fox News Sunday.

Cruz responded with a tongue-in-cheek tweet:

In honor of my friend @realDonaldTrump and good-hearted #Maniacs everywhere: https://t.co/KOPIi4XTVt

- Ted Cruz (@tedcruz) December 13, 2015

Trump's surprise success may have a shelf life after all, according to a new Iowa poll that puts Ted Cruz in a formidable lead.

Read: Ted Cruz Surpasses Donald Trump For First Time in New Poll

The conservative Christian from Texas is now crushing the reality TV billionaire by 10 points in the state, according to The Des Moines Register/Bloomberg Politics Iowa Poll.

Cruz, a Tea Party darling known for being an agitator within the U.S. Senate, leaped to the head of the pack with a record-breaking 21-point gain since the previous poll.

Per the influential poll, 31 percent of Iowans who are likely to attend the Republican caucuses said they back Cruz.

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