Newly installed campaign advisers are whispering to the GOP establishment that there will be a new Donald Trump , a more presidential, less bombastic Trump, a Trump who won't be an embarrassment to the party and lose to Hillary Clinton by double digits.

Don't bet on it.

On one level, there are an endless number of Trumps. His positions on issues from gay marriage to transgender bathroom use to erasing the $19 trillion debt in eight years change by the day, even by the hour.

He is as fluid on actual issues of policy as any candidate in recent memory. It would be little surprise if Trump got the nomination and immediately said his pledge to build a giant wall with Mexico and kick out 11 million undocumented immigrants was just a joke. He is not a candidate of serious policy. He is a candidate of celebrity, attitude and anger.

But on temperament, there is only one Trump. The real estate magnate can be briefly magnanimous and presidential in times of victory. Witness his short and buttoned down remarks following his win in New York. But when things go badly for Trump, he reverts to bilious tantrums almost instantly.

People seem to have so quickly forgotten Trump's rage storm after getting trounced in Wisconsin by Texas Sen. Ted Cruz . In a statement, Trump's campaign accused Cruz of campaign finance violations and raged against the establishment: "Ted Cruz is worse than a puppet," the statement said, "he is a Trojan horse, being used by the party bosses attempting to steal the nomination from Mr. Trump."

Trump is likely to do well in the mid-Atlantic primaries on Tuesday but he faces another potential loss to Cruz in Indiana, which will award 57 crucial delegates on May 3. The statewide winner will receive 30 of those delegates. And Trump has a razor-thin margin to get the 1,237 delegates he needs to lock down the nomination on the first ballot at the convention in Cleveland in July. Every delegate counts.

Does anyone expect that if Trump loses to Cruz in Indiana that he won't go completely bonkers yet again? And what if he falls well short of 1,237 delegates and Republicans refuse to simply hand him the nomination anyway? Will the "new" Trump take it in stride and pledge to abide by the rules and accept the will of the convention if they move on to another candidate on subsequent ballots? Not a chance.

And even if Trump somehow manages to contain himself, his rabid supporters are not likely to follow suit. Following Trump's complaints about a "rigged" system denying him delegates in Colorado and elsewhere, some Trump supporters are now issuing death threats to party leaders.

And this brings us to the next problem with Trump cozying up to the establishment and promising to bring his sky-high negative ratings down with a more traditional, policy-heavy campaign: his supporters will hate it.

Trump's entire rise to front-runner status was based on rallying blue-collar voters with promises to deport immigrants and block Muslims from entering the country all while raging against a president that many Trump's supporters still view as illegitimate. The last thing Trump Nation wants is a respectful campaign against Hillary Clinton in which their dear leader looks to broaden his appeal to women and minority voters. Talk about killing your brand.

But the real issue is that no matter what new advisers like Paul Manafort say to party insiders, Trump is who he is. He can contain himself in moments of victory. But when he loses, he rages like child sent to his room without supper. That's never going to change.

— Ben White is Politico's chief economic correspondent and a CNBC contributor. He also authors the daily tip sheet Politico Morning Money [politico.com/morningmoney]. Follow him on Twitter @morningmoneyben.

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