Republican presidential candidate Donald Trump gestures to a his camouflaged "Make America Great" hat as he discuses his support by the National Rifle Association at a campaign rally at the Redding Municipal Airport Friday, June 3, 2016, in Redding, Calif. (AP Photo/Rich Pedroncelli) ** FILE **
A man leaving a campaign rally for Republican presidential candidate Donald Trump squares off against protesters following him on Thursday, June 2, 2016, in San Jose, Calif. A group of protesters attacked Trump supporters who were leaving the presidential candidate's rally in San Jose on Thursday night. A dozen or more people were punched, at least one person was pelted with an egg and Trump hats grabbed from supporters were set on fire on the ground. (AP Photo/Noah Berger)
Republican presidential candidate Donald Trump, center, holds up a sign after autographing it during a rally at the Sacramento International Jet Center, Wednesday, June 1, 2016, in Sacramento, Calif. (AP Photo/Jae C. Hong)
Republican presidential candidate Donald Trump addresses supporters at a rally held at the Sacramento International Jet Center, Wednesday, June 1, 2016, in Sacramento, Calif. (AP Photo/Jae C. Hong) ** FILE **
In this March 1, 2016 file photo, Republican presidential candidate Donald Trump speaks during a campaign stop at the Signature Flight Hangar at Port-Columbus International Airport in Columbus, Ohio. China features prominently in the rhetoric of presumed Republican presidential candidate Donald Trump, who accuses the country of stealing American jobs and cheating at global trade. In China itself, though, hes only now emerging as a public figure, despite a notoriety elsewhere for his voluble utterances, high-profile businesses and reality TV show. (AP Photo/John Minchillo, File)
Supporters and bikers at a Rolling Thunder rally on the National Mall listen to GOP presidential candidate Donald Trump speak. The organization offered an invitation for candidates to speak, but only Mr. Trump accepted.
In this photo provided by ABC, Republican presidential candidate, Donald Trump, left, talks with host Jimmy Kimmel during a taping of the ABC television show, "Jimmy Kimmel Live!,” on Wednesday, May 25, 2016, in Los Angeles. Trump made an appearance as a guest, along with musical guest Greg Porter on the late night show, which airs every weeknight at 11:35 p.m. EST. (Randy Holmes/ABC via AP)
Republican presidential candidate Donald Trump applauds after singing the National Anthem during a rally at the Anaheim Convention Center, Wednesday, May 25, 2016, in Anaheim, Calif. (AP Photo/Jae C. Hong)