Is the American electorate going nuts? The 2016 presidential campaign is turning into the least rational in recent memory. Both leading contenders, Donald Trump for the Republicans and Senator Bernie Sanders (I-Vt.) for the Democrats, seem disturbingly out of touch with reality.Trump is a “candidate who will promise just about anything.” He has vowed to “be the greatest jobs president that God ever created,” have Mexico pay for a wall at the border, solve all US security problems, defeat Islamic terrorism and stop Iran from getting nuclear weapons once and for all. He promises this without a shred of supporting evidence about his ability to deliver — beyond his self-proclaimed business acumen and mastery at “the art of the deal.”Sanders’ campaign promises seem equally imaginary. His proposed single-payer health-care plan has been called “vague, unrealistic and irresponsible, a puppies-and-rainbows approach” and even left-leaning economists question the high costs of his proposals. His “political revolution” has been criticized as a dreamy fantasy blissfully oblivious to realistic constraints.The source of both candidates’ appeal is deeply psychological and rooted in the dynamics of wishful thinking. Each is tempting voters with highly alluring prospects that they passionately yearn for. Each exploits the inestimable powers of human motivation to bend reality to desire, thus sweeping rationality aside. The voters’ motivation derives from a reservoir of dissatisfaction that both candidates vow to replace with contentment.Here the similarity ends, however. Trump’s and Sanders’ campaigns couldn’t differ more both in the human needs they arouse and in ways they propose to address them.Trump appeals to people’s motivations for safety and comfort. His message resonates with people who struggle for subsistence or fear sliding back economically. They worry about losing their jobs to competition from immigration or globalization. Many might see themselves a paycheck away from homelessness. They feel insecure and abandoned by their leaders and society. They find Trump appealing because of his self-advertised power, his chest-thumping avowal that “he can!” protect them. His campaign exploits the psycho-dynamics of prevention and defense.Sanders invokes an entirely different desire: the need for people to feel that they matter and have personal worth and significance. It resonates with voters who yearn to change the world. Young idealists, perhaps, who set their sights on an impossible dream, on a utopia of justice and equality worth fighting for. Sanders invites voters to commit to a cause, proclaiming “they can!” pull off a revolution. His campaign thus rests on the psycho-logic of promotion and offense.Psychological research attests that when persons lose their personal sense of being in control, they often cede it to external agents: the federal government, a dictator, God. Trump supporters exemplify such yearning for a powerful protector.“They live in a childlike fantasy land,” one writer quipped, and “want a daddy, not a president.” Trump encourages a relinquishment of control that leaves it all up to him — because he proclaims himself the proven “winner.” His campaign exploits people’s resignation and their sense of frailty, whereas Sanders’ champions empowerment through commitment to a cause. Consider the respective demographics of Trump’s and Sanders’ supporters. Trump’s are older, less educated and earn less than the average Republican. About half are between 45 and 64 years of age, with another 34 percent above age 65 and less than 2 percent younger than 30. Half of his voters have a high-school education or less, and only 19 percent have a college degree. More than a third of his supporters earn less than $50,000 a year, while only 11 percent earn more than $100,000 a year.Sanders’ supporters skew far younger: Sanders beat former Secretary of State Hillary Clinton 84 percent to 14 percent among Democrats under age 30 in the Iowa caucuses. More than half his admirers are under age 35. They are also more likely to be unmarried, white, male and to have at least some college education. Unlike Trump, however, Sanders has also received strong support from voters making more than $50,000 a year.All in all, then, Trump’s supporters are older, poorer and less educated than Sanders.’ They are less likely to respond to a clarion call for “revolution” and more likely to seek help from a powerful benefactor.Both Trump and Sanders, however, have managed to harness the powers of essential human needs. This is the secret of their surprising success — never mind the unrealism of their proposals.Yet, the motives tapped by the two candidates diametrically differ. Trump admirers seek safety and comfort; they cower before an authority that vows to provide it. Sanders’ troops, meanwhile, “itch” to embark on activism that lends their lives purpose.Should both contenders secure the nomination of their respective parties, the 2016 presidential campaign would be headed for a polarization of unprecedented intensity. Because it is built on fantasies born of desire, however, the consuming fire in this case might produce appreciably little light — and the American people would be left to foot the bill. Arie W Kruglanski is Distinguished University Professor in Psychology at the University of Maryland, and a senior researcher at START, National Center for the Study of Terrorism and the Response to Terrorism. He is former editor of the Journal of Personality and Social Psychology: Attitudes and Social cognition, and of the Personality and Social Psychology Bulletin and is now President of the Society for the Study of Motivation