Donald TrumpDonald TrumpReport: Bannon told conservatives 'this is not a debate,' you have to back bill ObamaCare defeat caps difficult week for Trump Social media users troll GOP, Trump over ObamaCare repeal MORE is capping off a dramatic day of intense attacks against Republican primary rival Marco RubioMarco RubioSenators introduce new Iran sanctions Senate intel panel has not seen Nunes surveillance documents: lawmakers With no emerging leaders, no clear message, Democrats flounder MORE with a rally in Oklahoma City, Oklahoma. 

Earlier Friday, the GOP front-runner was endorsed by former White House candidate Chris Christie. The New Jersey governor is expected to stump for Trump in the lead-up to next week's Super Tuesday contests.