Story highlights "Whatever mistakes I made -- and I certainly made them -- probably wouldn't have changed the outcome," Bush said

Bush also had harsh words for whom he labeled Trump's "accomplice" -- the press

Washington (CNN) A reflective Jeb Bush said he had no regrets Thursday about his failed presidential bid, saying in his first interview since leaving the race that Donald Trump could still lose the nomination fight.

"There's a possibility that he won't get 50% on the first ballot," Bush told CNN's Jamie Gangel, giving his first television interview exclusively to CNN after dropping out of the presidential race in February. "And if he doesn't do that, there are a whole lot of people who don't believe he's the proper guy."

Bush, who has endorsed Texas Sen. Ted Cruz for president but been largely invisible as a surrogate, wouldn't say whether he would support Trump as the nominee in November, though he added there's no way he would vote for Hillary Clinton. When asked repeatedly how he would vote if Trump became the nominee, Bush responded, "I'm hopeful he won't be."

The former governor said only two people could win the nomination, seeming to not recognize the argument made by Ohio Gov. John Kasich that he could emerge as the nominee.

Bush said he observed Trump's foreign policy speech Wednesday with bewilderment, saying, "I don't think he is a serious person."

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