Graham: GOP will get 'slaughtered' if Trump nominee
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Sen. Lindsey GrahamLindsey Olin GrahamTrump shares Graham quote calling Ocasio-Cortez 'anti-America' Graham: Trump should focus on policy, not personal attacks The Hill's Morning Report - Presented by JUUL Labs - Trump attack on progressive Dems draws sharp rebuke MORE (R-S.C.) argued Wednesday that if Donald TrumpDonald John TrumpCNN's Camerota clashes with Trump's immigration head over president's tweet LA Times editorial board labels Trump 'Bigot-in-Chief' Trump complains of 'fake polls' after surveys show him trailing multiple Democratic candidates 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 RubioHillicon Valley: FTC reportedly settles with Facebook for B fine | Trump calls to regulate Facebook's crypto project | Court rules Pentagon can award B 'war cloud' contract | Study shows automation will hit rural areas hardest Court rules Pentagon can award B 'war cloud' contract later this summer Rubio asks White House to delay B Pentagon contract over Amazon concerns   MORE, Ted CruzRafael (Ted) Edward CruzGOP senators ask for federal investigation into social media companies' decision-making The Hill's Morning Report - Presented by JUUL Labs - Trump attack on progressive Dems draws sharp rebuke Ted Cruz blasts Tennessee GOP governor for declaration honoring early KKK leader MORE and John Kasich heading into Saturday's Republican primary in South Carolina, where he holds a considerable lead in the polls.