Graham: GOP will get 'slaughtered' if Trump nominee
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Sen. Lindsey GrahamLindsey Olin GrahamSenate Democrats pump brakes on new stimulus checks Comey, Rice, Clapper among GOP senator's targets for subpoenas amid Obama-era probe Schumer: GOP should 'stop sitting on their hands' on coronavirus bill MORE (R-S.C.) argued Wednesday that if Donald TrumpDonald John TrumpMinneapolis erupts for third night, as protests spread, Trump vows retaliation Stocks open mixed ahead of Trump briefing on China The island that can save America MORE is the GOP nominee, Republicans will get "slaughtered" in the November election. 

Lambasting the outspoken Republican front-runner as an "opportunist," Graham argued that Trump would kneecap Republicans' hopes of winning back the White House. 
 
"I think he's a kook. I think he's crazy. I think he's unfit for office," Graham, a backer of Trump rival Jeb Bush, said on Fox News's "America's Newsroom."
 
"I'm a Republican. and he's not. He's not a conservative Republican, he's an opportunist," Graham said on the program. "He's not fit to be president of the United States."
Trump pushed back against the broadside, sending several tweets arguing that Graham had no support before ending his own White House bid in December and "no cred" to make the claims.
 
"I will beat Hillary easily," Trump insisted in one of his tweets before going after Fox News for airing remarks from one of his critics on the program.
 
Trump is battling several rivals, including Bush, Marco RubioMarco Antonio RubioTrump administration designates B of PPP funds for community lenders The Memo: Trump's Scarborough tweets unsettle his allies House passes bill that would sanction Chinese officials over Xinjiang camps MORE, Ted CruzRafael (Ted) Edward CruzOn The Money: Trump signs order targeting social media firms' legal protections | 2M more Americans file new jobless claims, pushing total past 40M | White House to forgo summer economic forecast amid COVID-19, breaking precedent Trump signs order targeting social media firms' legal protections Overnight Defense: Trump ends sanctions waivers for Iran nuclear projects | Top Dems says State working on new Saudi arms sale | 34-year-old Army reservist ID'd as third military COVID-19 death MORE and John Kasich heading into Saturday's Republican primary in South Carolina, where he holds a considerable lead in the polls.