Political pollsters speak about the "threshold of acceptability" for a candidate. That's the pollsters' term for the various qualities of mind and character that voters look for first in a candidate before seriously considering him for national leadership.

Almost always listed by voters as threshold qualities that they value are honesty, competence, reliability and intelligence. But after watching the 1986 State of the Union ceremony, I believe that Ronald Reagan, especially for those brave souls who will seek to replace him in 1988, has now dramatically reconstructed the threshold of presidential acceptability.

Even the president's critics concede that Reagan obviously enjoys being who he is and doing what he is doing, an attitude Americans emphatically prefer over that of the long-suffering drudge. But Reagan's triumphant popularity cannot be simply attributed to an excess of cheerful optimism and thorough mastery of communications skills.

Yes, people like the messenger, but they also like his message. What Ronald Reagan, alone of recent chief executives, clearly possesses -- and what 1988 presidential voters will be looking for in George Bush, Mario Cuomo, Gary Hart and all other candidates -- is the genius of being comfortable with himself, of being emotionally secure.

Ronald Reagan has an extraordinarily high Emotional Security Index. Three examples of the Reagan ESI which come to mind. First, Reagan's hiring as his first White House chief of staff of James Baker, the man who helped manage the two previous Republican campaigns against him.

Emotionally, presidential campaigns are a foxhole experience in which the universe is unevenly divided between the very few, Us, arrayed against the rest of the world, Them. No other president, after the election, ever had a sufficiently healthy ESI to pursue a leader of the vanquished Them as indispensable to the victorious Us, until Ronald Reagan.

Then there was Reagan, the only president of the five who have served since 1968 to be so unthreatened by the ghosts of legend and history that he could award at a Rose Garden ceremony the medal of freedom to the family of the late Robert Kennedy.

Third, there was the secure Reagan graciously welcoming to the White House Jesse Jackson and Lt. Robert Goodman, the Navy pilot whose release from Syrian captivity Jackson had helped obtain. And then, as further proof of his strong ESI, the president accepted his own supporting role in the events of that day.

In spite of his own emotional security, the president remains too often the champion of the Deserving Rich, whose guiding premise seems always to be that Well-Off Uncle Oscar knows better. The goal of an enlightened national economic policy ought to be more than the comforting of the comfortable, and the president's persistent advocacy of a balanced-budget constitutional amendment -- while producing budget deficits of $711 billion over the last five years -- is no longer merely a frivolous deceit. It is now an aggravated assault on the intelligence of the body politic.

But ESI is important. Ronald Reagan's policies might have been wrong had he been president during the Vietnam war. But unlike at least one president we did have, he would not have used the rice paddies of Southeast Asia to earn the varsity football letter he had been denied in his own youth. Unlike a number of his failed predecessors who, it seemed, craved the presidency in order to be something, Reagan ran for president to do something.

His sense of self-worth does not hinge on his riding on Air Force One. If Reagan has truly reconstructed the threshold of presidential acceptability, what are the early returns on the ESI counts of his potential successors? Not terrific.

For example, George Bush has been a nifty and perky vice-presidential cheerleader, only to turn abruptly into a clumsy hatchetman, leaving the strong impression that he was uncomfortable with his old self and unsure of his new.

New York governor Cuomo, the main target of Bush's cheap shots, sought unconvincingly to elevate imagined ethnic slurs into his rationale for a presidential campaign. While Cuomo's ESI problems are not as severe as Bush's, they do merit attention.

As for Hart, if Ronald Reagan was the Teflon candidate to whom no troubles or setbacks attached, then Hart was 1984's Velcro candidate, to whom all knocks -- including the changes of name and age -- stuck like glue. But Gary Hart, because of events and his own political shrewdness (Who else could have turned an announcement of noncandidacy into a major three-day news event?) has the next six months more or less to himself to define publicly his candidacy and his vision of the future.

If Hart can handle those tasks, while simultaneously resolving the doubts about his character from 1984 then he can raise both his public ESI and his prospects for 1988, when, thanks to Ronald Reagan, all prospective candidates will be judged on their emotional index.