HEMPSTEAD, N.Y. — Donald Trump sought to evoke Ronald Reagan from his first answer in the presidential debate, but as he has throughout the campaign, he left out Reagan's elemental quality: optimism.

In Trump's words Monday night, American jobs “are being stolen from us,” blacks and Latinos are “living in hell” and America is “being ripped off by every single country in the world.”

The economy was “in a bubble,” he said, warning that it was “going to come crashing down” because of what he said were overly political actions being taken by the ostensibly apolitical Federal Reserve to buttress his opponent.

No uplift, no patriotic patois, no morning in America — not even a quick quip broke up the sequential references to a country falling apart at the seams. There was nothing, in other words, of the deft style that characterized the man Trump has evoked as a role model.

Trump's unrelentingly bleak assessment comports with the views of many of his ardent followers, who feel marginalized by economic and cultural changes afoot in the country.

Polls repeatedly have shown white voters to be more pessimistic than members of minority groups, older voters more pessimistic than the young, and non-college-educated whites — the group that has given Trump the strongest support — the most pessimistic of all.

But that pessimism runs counter to the sentiments of the broader general electorate that will judge Trump's fate in November.

Even in bad circumstances, Americans have been an optimistic people. Successful candidates, whether Republican or Democratic, have always taken heed of that in framing their political approaches.

While Trump's negativity is common in the kind of populist campaign he has waged, it is unprecedented in the annals of successful modern politicians. And it contradicts what research shows: Voters almost always will take optimism over pessimism.

Trump has espoused “a hammering, dystopian vision of what America is doing without much hope for what the future is going to be,” said Stanford University professor Neil Malhotra, whose research has looked at the connection between how successful candidates are and how optimistic voters perceive them to be. Candidates whom voters see as optimists generally do better, his work indicates.

Malhotra's research shows that among the most successful candidates at imbuing their politics with optimism were Reagan and Bill Clinton, two of the three two-term presidents in the last several decades.

Trump, by contrast, is more negative even than Richard Nixon, he said. Nixon is thought of in caustic terms because of the bitter way his presidency ended, but he ran on a platform of unifying the country during riot-torn 1968.

With humor and poetic rhetoric, Reagan set the standard for eviscerating an opponent while maintaining an optimistic mien. In his farewell address in 1989, he alluded to his frequent evocations of America as the “shining city” sought by all.

“Her glow has held no matter what storm,” he said. “And she's still a beacon, still a magnet for all who must have freedom, for all the pilgrims from all the lost places who are hurtling through the darkness, toward home.”

In tone, that is almost the direct opposite of Trump's call to wall off the country because of the threat posed by illegal immigration and terrorism.

Trump may be proceeding pessimistically in part because that's how he's succeeded so far. In the 2016 primaries, he successfully claimed the negative ground with a fierce attack on conventional politicians he accused of defending trade and other policies that he said had destroyed the middle class.

Other contenders — particularly former Florida Gov. Jeb Bush and Ohio Gov. John Kasich — put forward a sunnier, more inclusive rationale for their candidacies, but were trounced by Trump.

“Clearly he was tapping into an attitude that people have, an attitude that things are broken,” said pollster Lee Miringoff.

Malhotra, the Stanford political scientist, said that studies he undertook between 2010 and 2011 showed that Democrats valued optimism slightly more than Republicans, befitting a party that rallied behind the “Happy Days Are Here Again” theme even in the depths of the Great Depression.

But Republicans, too, reacted positively to rose-colored visions.

It didn't matter, broadly put, whether voters had a fully positive view of where the country was headed, or felt confident or not in the economy of the moment.

“One thing that was pretty constant,” he said, “People want their politicians to be more optimistic than themselves.”

cathleen.decker@latimes.com