Briarcliff Manor, New York (CNN) Donald Trump on Tuesday night sought to calm fretful Republicans bolting from his side over his latest controversy, laying out in measured terms his campaign platform and recasting himself as a "fighter" prepared to take on Hillary Clinton.

After days of characteristic defiance amid charges that his comments accusing a Mexican-American judge of bias were racist, Trump's speech Tuesday night marked an about-face as a more restrained, yet out-of-character Trump appeared.

Donald Trump turned to the two teleprompters to his left and right on Tuesday night and took a victory lap, as Republicans cast their final votes of the primary season.

He assured Republicans that he understands "the responsibility of carrying the mantle" and vowed to "never let (supporters) down." He welcomed Sen. Bernie Sanders' backers with open arms and he slammed Clinton as a deceitful politician who will never achieve the change Americans seek.

"I'm not a politician fighting, I'm me. You're going to see some really good things happen," Trump told a roomful of supporters and reporters at his golf club in the suburbs of New York. "Just remember this: I'm going to be your champion. I'm going to be America's champion."

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