Potential presidential candidate Donald Trump says he has "just a little" doubt that President Obama is U.S.-born but his feeling doesn't make him an "idiot."

The mogul and TV reality star suggested in an interview with ABC's "Good Morning America" that aired Thursday that he's reluctant to discuss the topic because "everybody that even gives any hint of being a 'birther,' a word you didn't use, even a little bit of a hint like, 'gee, maybe you know, just maybe there is this much of a chance,' they label them as an idiot."

Trump said that's not him.

"Let me tell you, I am a really smart guy. I was a really good student at the best school in the country. The reason I have a little doubt, just a little, is because he grew up and nobody knew him. When you interview people, if I ever got the nomination if I ever decide to run, you may go back and interview people from my kindergarten. They'll remember me. Nobody ever comes forward. Nobody knows who is he until later in his life. It's very strange. The whole thing is very strange."

Obama was born in Hawaii. He lived in Indonesia from the time he was six until age 10.

As for other presidential wannabes, Trump went through a list of potential 2012 contenders, giving one-line assessments of each.

Former Massachusetts Gov. Mitt Romney, he said, "doesn't seem to resonate." Former Minnesota Gov. Tim Pawlenty is not going "to captivate the voters." Former House Speaker Newt Gingrich is likeable because "he just joined my club." Former Alaska Gov. Sarah Palin made "a tragic mistake" by quitting her post early, but "is more qualified than Obama was" at the time he ran for the job. Former Utah Gov. John Huntsman is "disloyal" for leaving Obama's administration, where he was the U.S. ambassador to China, and running against him. As for former Arkansas Gov. Mike Huckabee, "I like him," Trump said.

"They're all good men," he added. "But you need somebody that is going to beat Barack Obama. You need somebody that's going to knock out Obamacare."

Trump is still undecided whether that will be him, but said he has one advantage to all the others.

"Part of the beauty of me is that I'm very rich," he said. He has indicated he's willing to put up $600 million of his personal fortune for a potential candidacy.

But one thing the "Celebrity Apprentice" host said he may not want to deal with as president, a weepy Republican House speaker.

"I don't like the crying," Trump said of Speaker John Boehner, R-Ohio. "I do not like it, I don't understand it. I really like him as a person. I think the crying is an emotional thing that, frankly, probably makes him a very nice man but, you know, I don't like to see it in a leader."