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Donald Trump is trying Ted Cruz's nickname on Hillary Clinton

Mark Abadi
Donald Trump

(Donald Trump.AP)
Donald Trump is floating a possible new nickname for his Democratic opponent — and it's one he's already used on a previous political rival.

"Lyin' Hillary Clinton told the FBI that she did not know the "C" markings on documents stood for CLASSIFIED. How can this be happening?" Trump tweeted Sunday night, referencing FBI findings released on Friday.

The nickname hearkens back to the Republican primary, when Trump repeatedly referred to Sen. Ted Cruz of Texas as "Lyin' Ted."

Trump's usual moniker for Clinton is "Crooked Hillary," though he has switched it up on occasion, calling the former US secretary of state "Heartless Hillary," "Unstable Hillary Clinton," and "Incompetent Hillary," at various times during this election cycle.

In June, he announced the launch of the website LyingCrookedHillary.com.

Some politicians fired back at Trump's tweet, because the "C" in question actually stands for confidential, not classified.

In another tweet, Trump mocked Clinton for her relatively poor showing in multiple national polls last week.

The tweet may also be a subtle jab at Clinton's health, a recent favorite topic of the Trump campaign. The brash billionaire has often asserted that Clinton lacks the "mental and physical stamina" to be president.

Clinton wasn't the only politician in Trump's crosshairs on Sunday. The candidate also lashed out at Arizona senator and fellow Republican, Jeff Flake, after Flake said he wasn't ready to endorse him.

NOW WATCH: Watch Hillary Clinton rip Trump's trip to Mexico

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