NEW YORK – Donald Trump puts a premium on loyalty and has proven unable to let a slight go by unchallenged. He touts the facts that he likes – and casts doubts on the ones he doesn’t.

While he has a penchant for exaggeration and an often tenuous relationship with truth, the Republican nominee has also shown himself to be a fighter who rarely cedes ground, even in the face of enormous pressure to do so.

If the New York billionaire is elected to the White House on Tuesday, it’s reasonable to expect the persona exposed by 18 months as a candidate for president will be the one he brings to the Oval Office.

“Early on, Trump was seen as someone who was going to stick to his guns no matter what. He was going to say what was on his mind. And you know he’s going to take the consequences of that no matter what,” said Ed Brookover, a former senior campaign adviser.

That remains, Brookover said, the essence of who Trump is today.

Trump has often said during the campaign he knows more than academics, generals and other experts, and he has largely forgone the kind of intense study sessions favoured by other candidates to learn about domestic and world affairs. He’s stuck by facts repeatedly debunked, the latest being his incorrect assertion that Democratic nominee Hillary Clinton wants to admit 650 million immigrants into the country – tripling the U.S. population “in one week.”

While he’s received briefings from U.S. intelligence officials, who have concluded Russia is behind the hacking of the Democratic National Committee, Trump routinely expresses doubt they were involved. “Our country has no idea,” he said during the third presidential debate.

Yet Brookover rejects the idea that Trump is a closed book unwilling to accept new information. He described a meeting this spring in Washington, at which Trump met with members of Congress who suggested he release a list of judges from which he’d select a nominee to the Supreme Court. Trump did so shortly after.

“He listens and takes in what people tell him a lot more than people give him credit for,” Brookover said.

Trump is also a candidate who appears incapable of ignoring a slight and is all too willing to respond with disproportionate force.

The day after accepting the presidential nomination at his party’s convention, he taunted dispatched rival Ted Cruz rather than focus on the general election campaign that had just begun. He’s put his standing among women and military families at risk by doubling down on his replies to the criticisms levied by the parents of a slain Army officer and a Latina beauty queen he shamed for gaining weight.

“I’ve been saying during this whole campaign that I’m a counter-puncher,” he once explained to Fox News Channel star Megyn Kelly, among those Trump has tangled with during the campaign. “I’m responding. Now, I then respond times maybe 10. I don’t know. I mean I respond pretty strongly. But in just about all cases, I’ve been responding to what they did to me.”

Eric Trump, one of Trump’s sons, cast his father in an interview as David taking on Goliath largely on his own.

“He’s had to take on the DNC, take on the corruption, a very, very biased media in so many cases,” Eric Trump said of his father. “He’s done that all by himself and me and quite frankly the American people. … I give him tremendous, tremendous credit because he shouldered so much weight on his own. He shouldered a movement to change this nation.”

While the presidential campaign is undoubtedly intense, the patterns of behaviour Trump has displayed as the Republican nominee are likely to continue, said Ari Fleischer, who served as press secretary to President George W. Bush.

“The campaign is a great indication of what will happen in a White House,” he said. While Trump has shown the ability to moderate, Fleischer said his counter-punching instinct could be “a disaster in the Oval Office,” where calm and level-headedness are crucial when something goes wrong.

“It would be even worse if he does it with majesty and the power of the presidency on his hands,” he said.

But friends and former aides, among them those who have known Trump for years, say the celebrity businessman defined by his boisterous campaign rallies is very different behind closed doors. Former neurosurgeon Ben Carson, a former rival-turned-supporter, has described “two different Donald Trumps.”

“There’s the one you see on the stage and there’s the one who’s very cerebral, sits there and considers things very carefully,” he said during a recent endorsement speech.

Former House Speaker Newt Gingrich, another Trump adviser, put it another way. With the risks of Trump saying things that are unwise comes, too, the benefits of a leader who is a “truly a historic figure” able to effectively communicate his ideas to millions of people.

“So, it’s a funny paradox,” Gingrich said Sunday on NBC’s “Meet The Press.” ”On the one hand, he’s one of the most brilliant marketers I’ve ever seen. And on the other hand, for a while there, he was undercutting himself. I suspect if he had not done that, he’d be ahead by ten or 15 points right now.”

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