Donald Trump Defends Linking Ted Cruz's Father to JFK Assassin

— -- Republican front-runner Donald Trump today refused to apologize for citing an unsubstantiated report that Ted Cruz's father was photographed with the assassin of former President John F. Kennedy, saying no one has ruled it out.

"I don't think anybody denied it," he told ABC News' George Stephanopoulos on "Good Morning America.”

Cruz and his father both denied the report Tuesday before Cruz dropped out of the 2016 race after losing the Indiana primary. The National Enquirer had published a story several weeks ago alleging that Rafael Cruz was pictured with Lee Harvey Oswald, but the story has not been corroborated.

"It's ludicrous. It's ludicrous. I was never in New Orleans at that time," Rafael Cruz told ABC News Tuesday. "That's typical of Donald Trump; just attack and make all kinds of innuendo and attacks with no substance."

Ted Cruz said, "Let's be clear. This is nuts.”

"This is not a reasonable position,” he told reporters Tuesday. “This is just kooky. And while I'm at it, I guess I should go ahead and admit, yes, my dad killed JFK, he is secretly Elvis and Jimmy Hoffa is buried in his backyard."

Trump originally brought up the allegation Tuesday morning. "I mean, what was he doing with Lee Harvey Oswald shortly before the death, before the shooting?" Trump asked. "It's horrible."

But Trump, who now faces an easy path to the Republican nomination, defended his comments.

"All I did was refer to it. I’m just referring to an article that appeared. It has nothing to do with me," he said. "The National Enquirer gave you John Edwards. It gave you O.J. Simpson. It gave you many, many things. I mean, you can’t knock the National Enquirer. It’s brought many things to light."

In the same interview, Trump said that he would accept small contributions in the general election, but didn't want big contributions.

"We will probably take small contributions," he told Stephanopoulos. "I don't want to have anybody have any influence over me, that I can tell you." Trump has insisted for months that he is financing his own campaign, and he has loaned himself most of the dollars he spent in the primary.

He added that his vice presidential pick would be a Republican, "most likely" an elected official who has political experience to work closely with Congress.