Sen. Ted Cruz of Texas has taken a substantial lead among Republican presidential candidates in the Iowa caucus, leading second-place Donald Trump by 10 percentage points in a new survey released Saturday night.

The Des Moines Register/Bloomberg Politics poll confirmed a recent trend that has shown Cruz gaining in the state, which holds the first contest in the presidential primary and generally supports culturally conservative candidates in its Republican caucuses. A poll released earlier this week showed Cruz leading Trump by 5 percentage points.

Trump and retired neurosurgeon Ben Carson had led in most other polls taken in recent months.

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The poll released Saturday showed Cruz as the first choice for 31% of those who responded, with Trump having support from 21% and Carson coming in third with 13%. Sen. Marco Rubio of Florida, with 10%, was the only other candidate in the double digits. Cruz also led all candidates when voters were asked for their second-choice candidate, underscoring his strength in the state.

The telephone poll of 400 Republican voters who said they will definitely or probably attend the Feb. 1 caucuses was taken Monday through Thursday, meaning many if not all of the interviews took place after Trump called for barring all Muslims from entering the U.S. It has a margin of error of plus or minus 4.9 percentage points.

The polling firm, Selzer & Co. of Des Moines, is considered one of the best at predicting the state, which is notoriously difficult to poll accurately.

Pollster J. Ann Selzer, speaking to the Register, called the results a “big shake-up.”


noah.bierman@latimes.com

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