"If I have a choice — and you can put it in bold — if I have a choice between Trump and Hillary Clinton, I'm choosing Hillary," Miami healthcare magnate Mike Fernandez told the Miami Herald on Friday. "She's the lesser of two evils."

Outraged by Trump's unimpeded ascent, Fernandez is taking on the GOP frontrunner himself. He purchased a full-page ad in the upcoming Sunday edition of the Herald calling Trump a "narcissistic BULLYionaire with a hunger to be adored." He also likened him to some of history's bloodiest demagogues.

"You have no idea how furious I am with my friends in the Republican Party who have embraced this guy," Fernandez said.

Fernandez, who also plans to run the ads in Des Moines and Las Vegas newspapers on Dec. 14, said he didn't notify the Bush campaign of his plans. Fernandez was the single highest donor to the political committee backing Bush, Right to Rise USA, as of the last financial disclosure report at the end of June. His contribution: more than $3 million.

"My frustration is really with that sector of Republican voters that are so blinded by the demagoguery" of Trump, Fernandez said. "I know the campaign — or any other campaign — is not going to say it.... This is not about Jeb. This is about us. This is about the voter."

By saying he'd pick Clinton over Trump, Fernandez took a bolder stance than Bush himself, who said on CBS News' Face the Nation last Sunday: "Anybody is better than Hillary Clinton," though he added that he has "great doubts about Donald Trump's ability to be commander in chief."