Donald Trump won't rule out third-party bid

(CNN)Donald Trump upended the much-anticipated prime-time Republican presidential debate within the opening seconds.

When asked for a show of hands from anyone who would not rule out a third-party bid, Trump was the only one of 10 candidates on stage to raise his hand.
"I can totally make the pledge if I'm the nominee," Trump said, referring to pledging to support the nominee.
Trump has repeatedly declined to rule out a third-party White House run, saying in an interview with CNN's Anderson Cooper that he's constantly being asked to run as an independent.
    Last month he told The Hill that his decision will depend on "how I'm being treated by the Republicans."
    Ralph Nader has previously advised the Republican party to not push Trump to run for a third party nomination.
    Nader has run for president multiple times as a third-party candidate and may have cost Democrat Al Gore the 2000 election by running to his left.
    "The Republican Party establishment is playing with nitroglycerine when it goes after Donald Trump and tries to minimize him and exclude him," Nader told CNN in an interview. "Because a jilted Donald Trump as a third-party candidate can blow the presidential race wide open and turn it into a three way race."