WATCH LIVE: Trump holds rally amid escalating feud with Rubio

Donald TrumpDonald TrumpTrump: ‘I’d love to debate Bernie’ to raise M for charity Trump: aide was "misquoted" in article about VP pick Vincent Foster's sister: 'Cruel' for Trump to bring up death MORE is capping off a dramatic day of intense attacks against Republican primary rival Marco RubioMarco RubioRNC official defends Susana Martinez after Trump criticism GOP Senate hopeful wants to go beyond Trump's Muslim ban Trump clinches GOP nomination 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.

More in News

WATCH LIVE: Trump speaks at NRA forum

Read more »