Former Republican rival Ben Carson backs Donald Trump for White House bid

Former rival Ben Carson has backed Republican presidential frontrunner Donald Trump, becoming the second former presidential candidate to support the billionaire businessman in the race for the White House.

Carson, a retired neurosurgeon who dropped out of the race on March 4, follows New Jersey governor Chris Christie, a former candidate who also backed Trump after earlier dropping out of the race for the party’s nomination ahead of the November 8 presidential election. Carson made the announcement at a joint news conference with Trump in Florida, ahead of that state’s primary on Tuesday.