COLUMBUS, Ohio -- As Donald Trump denied he ever seriously considered John Kasich as his running mate, the Ohio governor was leaving the door open for an endorsement of the GOP presidential nominee.

The New York billionaire's heated rhetoric has turned off many party faithful, including Kasich. But don't expect to see a "Republicans for Hillary" sign in Kasich's yard anytime soon.

"I'm not voting for Hillary Clinton under any circumstance," Kasich told reporters at the Ohio State Fair.

What about Libertarian candidate Gary Johnson, a former Republican New Mexico governor? Too early to say, Kasich said.

He had no comment on Trump's plans to fund a political action committee against a future Kasich presidential run. He spoke to reporters at about the same time Trump denied, again, that he approached Kasich to run for vice president.

A Kasich spokesman had no comment Wednesday on Trump's remarks. Kasich didn't mention Trump Wednesday morning but said the top of the ticket will have an impact on down-ticket races.

Kasich plans to help candidates for U.S. Senate and Congress, including Arizona Sen. John McCain and Illinois Sen. Mark Kirk. How much time will he spend on the campaign trail? Depends on how many candidates want him, he said.

Kasich said again that he has no regrets about not addressing the Republican National Convention last week in Cleveland, an atypical decision that's drawn criticism. Kasich said it would have been inappropriate to speak at the convention without endorsing Trump.

"You have to always follow your conscience in politics and if you don't then you end up regretting," Kasich said. "I have a message of unity that's pretty darn clear and pretty well defined and I intend to continue with that message."