New Iowa Poll Shows Ted Cruz and Donald Trump in Tight Battle

The Texas senator and real estate mogul are running about even in Iowa.

Cruz's strong standing in Iowa is largely thanks to support from tea party backers and evangelical Christians. Still, likely GOP caucus-goers choose Trump as the best candidate on the economy, terrorism and illegal immigration. Trump also earns more support from men and from voters without a college degree.

Cruz and Trump have been sparring with each other over the last week, as Trump raises questions about whether Cruz is a "natural born citizen" and eligible to be president. Cruz was born in Canada to an American mother and Cuban father. Most experts say he is eligible to hold the office, but it has never been decided by the Supreme Court.

Trump leads national polls by a wide margin. He also leads in New Hampshire by double digits over a splintered field of establishment candidates. Still, Cruz has recently been a favorite to win the Hawkeye State, thanks to support among tea party backers and evangelical Christians.