Trump's threat to go third-party angers some in GOP

In an interview with MSNBC’s “Morning Joe” on Friday, Mr. Trump did not back away from the threat to wage an independent bid. “I’m a natural negotiator, and I like leverage,” Mr. Trump said. “If somebody gets in that I like and if I’m treated with respect, I would not run as an independent. But I want to leave the option open, just in case that doesn’t happen.”

Most Republicans are reluctant to attack Mr. Trump or pressure party leaders to force him from the main stage in the next candidates’ debate in California in September in part because they want to win over his supporters if he falters. Even Mr. Trump’s detractors and rivals for the nomination said it would be futile to pressure him.

“The more you attack Donald Trump, the better he does,” Louisiana Gov. Bobby Jindal, one of his rivals, told reporters Friday at the Red State conference.