Story highlights Paul said he has concerns about both Trump and Cruz, attacking both of them on foreign policy

He also attacked Cruz for flip-flopping on issues based on what's politically expedient

Washington (CNN) Forced to choose, Sen. Rand Paul says Donald Trump potentially becoming the Republican presidential nominee is more worrisome than Sen. Ted Cruz -- but he took plenty of shots at both of them on Thursday.

The Kentucky Republican is languishing in the low single digits in the polls as Trump and Cruz lead the pack in the GOP primary, but Paul said the prospect of a Trump presidency concerns him.

"I do worry a little bit more about Donald Trump," Paul told CNN's Wolf Blitzer on Thursday. "The main reason I do is that I believe he wants more power to come to him and 'he'll take care of us all' if we just give him more power, but I'm from a limited government tradition."

The attack was an echo of attacks Paul made Wednesday, including comparing Trump to Gollum, a villain from "Lord of the Rings" who is corrupted by his quest for the powerful ring.

"I think what Trump wants is bad for America," Paul said.

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