Story highlights John Kasich said Sunday that he doesn't believe Donald Trump will be the GOP nominee

Kasich said that he doesn't "necessarily believe what I see" that Trump leads the polls

Washington (CNN) Ohio Gov. John Kasich is predicting that Donald Trump will soon fade from the top of GOP presidential polls as voters look for "somebody who has the experience."

In an interview with CNN's Jake Tapper on "State of the Union," Kasich, a Republican presidential candidate, said he isn't buying polls that show Trump in the lead -- including a new CNN/ORC poll that puts the real estate mogul's support at 36%, more than double any other contender, among Republicans.

"I don't necessarily believe what I see because it's not a poll of likely voters," Kasich said, adding that he's not convinced many of those who say they support Trump will ultimately vote for him.

Kasich also defended his ad featuring a former U.S. prisoner of war, Col. Tom Moe, which some have said recalls the famous poem "First they came ..." written by Pastor Martin Niemöller about Nazis, while highlighting groups Trump has attacked.

The Ohio governor denied the ad was meant to compare Trump to Adolf Hitler, but defended the tenor of the ad.

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