Graham: GOP will get 'slaughtered' if Trump nominee
© Getty Images

Sen. Lindsey GrahamLindsey Olin GrahamSunday shows preview: Lawmakers gear up for Senate impeachment trial Parnas pressure grows on Senate GOP Senate GOP mulls speeding up Trump impeachment trial MORE (R-S.C.) argued Wednesday that if Donald TrumpDonald John TrumpTrump's newest Russia adviser, Andrew Peek, leaves post: report Hawley expects McConnell's final impeachment resolution to give White House defense ability to motion to dismiss Trump rips New York City sea wall: 'Costly, foolish' and 'environmentally unfriendly idea' 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.