Republican presidential candidate John Kasich adjusts his tie as he poses for a photo with supporters before a meet-and-greet at the Arthur Avenue Market in the Bronx on April 7. (Carlo Allegri/Reuters)

John Kasich has run his presidential campaign on the premise that he is the gentler, reasoned choice. He’s the candidate who hugs voters. He’s the one who calls for tolerance and softer rhetoric. And Tuesday, he laid out in sharp terms the choices before Republican voters: a descent into darkness with Donald Trump or Ted Cruz, or a sunnier path with him.

“A political strategy based on exploiting Americans instead of lifting them up inevitably leads to divisions, paranoia, isolation and promises that can never, ever be fulfilled,” Kasich said. “I say to you that this path to darkness is the antithesis of all that America has meant for 240 years.”

But Kasich’s lighter approach has earned him little more than the distinction of the last so-called establishment Republican left to challenge Trump and Cruz. Kindness has not proven to be a winning strategy.

Even Democrats Bernie Sanders and Hillary Clinton, who once were seemingly above personal attacks (people don’t want to hear about “your damn emails”), recently took to the kind of bitter sniping that has become inevitable in a competitive political race. They questioned the other’s bona fides to be president. Sanders questioned Clinton’s integrity while Clinton has suggested that Sanders is not a “real Democrat.”

And though they’ve since toned it back down, their rift illustrated that the oft-promised collegiality among campaigns rarely lasts long. In politics, and in life, there’s a dog-eat-dog mentality about success. Leadership has long been associated with someone who is dominant, authoritative and stands his or her ground.

But such traits are not the best way to earn success outside of politics, said Emma Seppälä, a Stanford psychologist and author of The Happiness Track: How to Apply the Science of Happiness to Accelerate Your Success.” 

There is an emerging field of research called “positive organizational psychology” that has found that the cutthroat, aggressive behavior some people use in the workplace is ineffective for earning respect. Rather, compassion and humility breed loyalty and engagement, which then yields greater success.

That doesn’t mean being a doormat or letting people walk all over you, said Seppälä, who is also science director of the Center for Compassion and Altruism Research and Education at Stanford’s School of Medicine. But a leader can be strong without being cruel.

For bosses who are unkind, their employees actually have a physical reaction in the brain when they recall interactions with them, according to a 2012 brain-imaging study published in the Leadership Quarterly. Thinking about those negative bosses activated the part of the brain associated with negative emotions and avoidance.

“This is the thing — from birth to death, the most important predictor of happiness and physical health is positive relationships with other people,” Seppälä said.

But then why are people like Steve Jobs, who was notoriously a jerk, so successful? Why does Trump’s negativity resonate? There are established correlations between so-called dark personality traits like narcissism and career success. There is still some truth to nice guys finishing last.

“We put a lot of value in aggression in our culture,” said Johann Berlin, who coaches business leaders on taking a kinder approach in the workplace. Yet research has shown that people have a stronger propensity for kindness. They respond better to it. It’s actually in our nature to be nice.

Dacher Keltner, a psychology professor at the University of California at Berkeley, has studied the impact of kindness of productivity. In fact, a study he co-authored last year measured U.S. senators’ success based on their virtuousness. Those who exhibited “greater courage, humanity and justice” had more influence. Moreover, those who were Machiavellian in their approach were unsuccessful, particularly in leadership roles.

“Senators who displayed a lack of empathy and a competitive orientation toward other people (i.e., psychopathic traits), in particular, were unlikely to garner support from their peers after they became leaders,” according to the study.

The study concludes by urging voters to support the “virtuous candidate” in an election. Of course, that doesn’t seem to be resonating, at least not among Republican primary voters. Keltner, who has a book coming out next month called “The Power Paradox: How We Gain and Lose Influence,” said Kasich’s lack of traction is in part because of society’s view of an archetypal leader.

“One is our stereotypes of power, which presuppose that kindness is for the weak, but in fact many studies show that kindness is a basis of enduring power and the esteem of others,” Keltner said. “Second, there has been a long-standing bias against kindness more generally in our culture: Kindness may be devalued because it is assumed to be weak and blind.”

Although many have heralded Kasich’s kindness, it has also been seen as a disadvantage. Voters want to see someone whom they can picture going toe-to-toe with adversaries. When asked about this a few weeks ago, Kasich said, “I think nice usually wins,” according to a New York Times story about his temperament. But then he added, “Most people have a sense that when the time comes to fight,” he said, “I’ll fight just fine.”

 To that end, if Kasich were the one nipping at Trump’s heels instead of Cruz, most expect he’d be slinging mud like the rest of them. It’s biological to fight back.

“This doesn’t happen in a vacuum,” said Dannagal Young, a communications professor at the University of Delaware. “When someone attacks you unfairly, at some point, there is a fine line between defending oneself and attacking another. If someone threw something your way, it’s a natural inclination to say, ‘P.S. look in the mirror. What about you?’ ”

But the most effective leaders can do both. It’s possible to defend oneself without spite. It’s even possible to be angry without being mean.

This campaign season definitely makes it seem as if kindness can’t win. And maybe this year it won’t. But remember, too, that while Trump may be ahead in the GOP primary, about two-thirds of American voters view him unfavorably.

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