Six days before D-Day - Election Eve: John Deardourff is all managerial cool in a roomful of aides, "manics" as he calls them, who gulp their cups of black coffee in time to jangling phones.

What's to worry? Only millions of dollars, months of work, his reputation as a political consultant - to say nothing of the futures of the half dozen major Republican candidates around the country Deardourff hopes to help keep in or sweep into office.

Deardourff, 45, looks Ivy League, together - herringbone jacket, rep tie, gray slacks, glisteningly polished brown shoes, an antiseptic smell from an after-shave lotion, no bags under the eyes. And yet Gov. John Rhodes of Ohio had awakened him out of a sound sleep at 10 to midnight with one phone call. And another at 6:55 a.m. (Deardourff remembers exact times.) Rhodes gave no greeting, just an order: "I want two spots on every station at prime time for the next four nights!"

And so Deardourff, dancing to the tune of his six-figure salary (during an election year), was moving out of the U.N. Plaza Hotel and into the New York penthouse rabbit warren offices of Bailey, Deardourff & Associates, Inc.

Into the phone went a Deardourff tough command, chilling in its soft delivery: "The place to add if we can buy more time is the Cleveland market." There's trouble in River City. The polls show Rhodes down slightly in Cleveland.

Deardourff grabs another phone. Pollster Bob Teeter will fly into Cleveland to rendezvous with Deardourff about the outlook in Michigan and Ohio. Watches are synchronized. Deardourff can't get there until 4:30 p.m. He wants to return at 8 to New York. In one five-day period he logged 15,000 miles - Florida, Venezuela, Ohio, Michigan, New York, Pennsylvania. Does he ever get scared of flying? "Yeah - but I suppress that too."

Tuesday night early returns show Rhodes leading in Ohio and Deardourff lets out a whoop, "Oh, oh yeah! The old boy's gonna do it. He's the American gothic of American politics."

But by midnight, the race was still a cliff hanger. It had been a fine night for Deardourff. Wins in Michigan, Pennsylvania, Iowa, a projected win for Rhodes. Partner Doug Bailey had just show big in Illinois with Sen. Charles Percy and Gov. Jim Thompson.

And so Deardourff was at his most expensive in his Virginia home. In white baggy cords and blue sweater, he raced from the constantly ringing phone to a TV set, drinking white wine, eating cake, tallying his wins on a yellow legal pad, chortling as the night wore on. He watched the results of his colourful campaign on a black and white television set, unable to distinguish the blue Republicans from the red Democrats on the maps.

A little after midnight, Rhodes talks to Deardourff, shouting with a hoarse voice into the phone, "We're gonna make it, Jonathan!" Walter Cronkite is droning on the set that the Republicans had gained at least two seats in the Senate. Deardourff waits until 1:30, when they declare Rhodes the victor.

At 11 p.m. Deardourff's 2-year-old daughter, Megan, wanders out of bed. His wife, Betsy, stops doing her Christmas needlepoint stocking to hug her.Deardourff starts to talk about how he witnessed her natural childbirth - and then, for the umpteenth time, the phone rings.

It is, Betsy says, a normal election night. 'Why Is This Man Smiling?'

Deardourff and Philip Angell are gloating over one of their final anti-Carey ads, watching on a TV in a cubbyhole of the New York office. To the tune of "East Side, West Side," a picture of a smiling Gov. Hugh L. Carey flashes on the screen. The voice-over says that with New York in the trouble it's in, "why is this man smiling?" Carey is in black and white. Duryea is in beautiful silver (hair) and beautiful blue (sweater).

Then comes the carefully crafted litany of Carey "negatives": "Since Carey became governor, crime has gone up 24 percent. Over 700 companies have shut down or moved out. State taxes have increased $166 for every man, woman and child in New York. . ."

David Murray Carey's press secretary, scoffs. "Violent crime has dropped, except in rape and tha's because the recording procedure has been simplified and more women are reporting rape. About those companies moving out: A company starts to make those moves five years before they do. Under Carey, many are coming back. The fact is 160,000 new jobs have been created. That $166 in taxes is mostly local over which Carey has no say. Deardourff is good at turning a kernel of truth into an ear of corn - and I do mean CORN!" Negative Ads

This year, media political wizards have often stressed the negatives of the other candidate, rather than the positives of their own. Some critics feels this was a Deardourff mistake in New York - that people felt negatively enough about Carey without Duryea dumping on him.

Sometimes the negative can mean only positive results for an opponent.

In Michigan, Gov. William Milliken's opponent, state Sen. William B. Fitzgerald Jr., slashed at Milliken with some vicious ads that implied that blindness, hair falling out, "brains growing outside the head" were happening to humans because of the state's alleged mishandling of the contamination of cattle feed by the chemical PBB. Editorials all over the state called the ad - a "new low" in dirty politics. The ads was pulled but Milliken's aides and their consultant, Deardourff, swooped down on those editorials, put them in an ad and presented Milliken as the nicest, cleanest guy around. (On election day Milliken was ahead three points.

Milliken was Deardouriff's first victory, shortly after the polls closed, followed by Gov. Robert Ray of Iowa, Duryea was his only loss. As a smiling Carey hits the TV screen, Deardourff Monday-morning-quarterbacks and says he didn't expect Duryea to win three weeks ago.

"After Carter's Camp David meeting, we started to loss the Jewish votes. . ." On the phone to a reporter, Deardourff says, Carey did not rehabilitate himself. We only managed to reduce Duryea to his level." He rapped Duryea for not taking advice to disclose his financial statements, and for what Deardourff regards as some staff campaign incompetence.

"In this case the advertising was much less important on either side than what was happening. (At least $2 million was spent for ads by each candidate.) We were trying to say of Duryea 'When he gives you his word, you can count on it,' while at the same time Duryea is equivocating and unwilling to be forthcoming on income taxes."

Deardourff says he and partner Bailey are good at "giving expression to abstract, complex and sophisticated ideas in a simple, visual way." A Rhodes ad shows an old-fashioned cash register. When it goes 'ping,' up shoots not a number, but the head of Rhodes' opponent, Lt. Gov. Richard Celeste, to suggest that there would be higher taxes under Celeste. Rhodes also attacked him as a "fuzzy-wuzzy liberal." (On election eve some polls showed them tied, others with Rhodes slightly ahead.) Really Satisfactory Win

"Deardourff is damn good at taking mediocre Republicans, like Thornburgh, and running them against Democrats," says one political observer. Lagging badly in early October, Richard L. Thornburgh, Pennsylvania's gubernational hopeful, hammered in TV ads that his opponent, Pete Flaherty, former Pittsburgh mayor, did little for Pittsburgh. "Can the man who drove Pittsburgh to its knees put Pennsylvania back on its feet ?" was the Deardourff crafted slogan. (Once written off as a sure loser, Thornburgh went into Tuesday night close.)

To Deardourff, Thornburgh was the really satisfactory win and TV commentators who had written him off months ago were now on election night talking in respectful tones. During the primary, Deardourff recalled, as Thornburgh is declared the winner, nobody in Philly knew who the guy was. They didn't even know his name."

By 11:15, Deardourff is on the phone to Thornburgh, "Hey! I don't suppose on some obscure corner of the capitol grounds I could have a statve? Well, I'm proud of YOU. All you've got to do is produce. We've got you this far. Bailey and I are now tallying a win of nine to one and none of them was more exciting than your race.Then to Thornburgh's wife, "Ginny, how are you, dear? You're the next first lady of Pennsylvania!" The Best of Gerald Ford

Deardourff is best remembered for his superb handling in 1976 of what was then regarded as the Republican's premier mediocre candidate, Gerald R. Ford. In only 77 days Ford went from an astounding 20 percentage points behind to come within 10,000 votes of winning. Deardourff will spend hours rapping as if doing an interview with a candidate - as the film rolls along - to capture maybe three minutes of the best of those hours. In this way he captured the best of Gerald Ford - his basic decency. As Democratic consultant Mark Shields says, "It was masterful in its simplicity: the old shoe against the new suit." And then the negative zinger voiced reasuringly in those ads: "And if you have a couple of doubts about the new guy, why not listen to what a few other Americans just like you think. . ."

When Bailey and Deardourff teamed up 11 years ago, they were among the first to use the man-on-the-street endorsement - now taken to such a ridiculous degree by commercial products, from underarm deodorants to toilet paper. Those political testimonies are being done by every consultant now, so that the entire world looks like a paid cast senior citizens who all love their favorite candidate. Deardourff says because of the saturation, they're moving away from that.

But he doesn't mind being bored. "If something works I never have any problem doing it again. Hell, it's like a guy hitting golf balls. It may be boring, but if you're hitting 290-yard drives, you don't change you grip."

One of his skills, says Deardourff, is "being able to understand and analyze the mood of the voter." (Some critics say he goofed with Ken Maddy, who lost in the California primary because they did not perceive the intense interest in Proposition 13.) In spots for Gov. Ray of Iowa, Deardourff talks about pride in Iowa. "That kind of commercial would be totally inappropriate in New York City. Nobody's got pride in NYC."

Some Rhodes spots show the governor leading the Ohio state fair band. The flag - in all its red-white-and-blue glory - flies in one corner of another ad. It may be corny, but, says Deardourff, 'That's Ohio.' Small-Town Boy

Deardourff knows what is Ohio because underneath the sophistication, the smoothness, the ambition is a small-town Ohio boy. One who was always very competitive.

Deardourff wanted to play tennis. So he practiced for hours against the garage wall. But there wasn't anyone to play tennis with. So he would hitchhike to Dayton to play. He was soon winning tournaments.

"I get a little bored with the analogies between politics and sports but nevertheless I think there are some parallels. I won varsity letters in four sports," says Deardourff, 6 feet tall and 195 pounds. He offers a slight laugh. "A perfect tight end."

His father ran a small-town daily paper in Greenville, Ohio, his mother was a nurse and, "Between the two of them, I don't think they made more than $10,000 in any given year."

It was secure, small-town living. Politics was a part of his life at home - politicians usually like to get to know small-town daily newspaper editors - Then came Wabash College and the Fletcher Graduate School of Law and Diplomacy. After graduating Deardourff moved comfortably into working on both campaigns for John V. Lindsay and Nelson A. Rockefeller, where he met partner Doug Bailey.

An early marriage ended in divorce - "a combination of immaturity on my part and a classic case of two people marrying before one or the other knew where life was going." He is now married to Betsy Griffith, 30, active in the feminist movement, now turning a Phd. into a book. Deardourff thinks it not unlikely he will someday run his wife's campaign for some office. White-Hat Clients

It is a slightly set-righteous phrase in the Bailey-Deardourff literature: Their services are "available to candiates we wish to see in public office." Deardourff makes quite a thing of taking on only clients of the white hat variety, and mostly moderate Republicans.

However, for a man who supports the ERA and the right to choice on abortion, for example, he had at least three candidates this year who have taken anti-abortion stances. Once critic says, "John and Betsy do this cute feminist couple routine. If he's such a huge feminist, how can he support John Porter, strongly for the Hyde amendment and a plastic Republican backed by conservative businessmen? And against Ab Mikva (Porter's Illinois opponent) who is right on all the issues Deardourff says he stands for. Porter is one of the few in a congressional race who can afford Deardourff. John'll take anyone who will give him money and will not destroy his image of the moderate Republican image maker."

Deardourff says Porter is his partner's client and that he knows nothing of his record. Deardourff glides over anti-abortion votes of other candidates by saying that he avoids plugging that stance in the ads. He looks for an overall feeling that the "people for whom you work are good people. You can't demand 100 percent conformity with your own personal views." He doesn't mind flakking Duryea's death-penalty stance "because I have no strong views on that, one way or the other.

Deardourff does get angry. Philip Angell, an aide says, "I'm a screamer myself. His tone just gets harder, say, when you deliver a stupid suggestion at a time when the pressure is on. One Duryea spot, I suggested a title and he said, "That's just stupid. It'll destroy the whole tone of the spot."

Deardourff says what makes him angry is "incompetence and moral eunuch." Winning Counts

In a game where winning means the difference between staying alive and collapsing as a consultant, working for Republicans can be chancy. This year was a crucial one for the weakening GOP. But people say Deardourff generally picks his Republicans wisely. "Although the number of voters who think of themselves as moderate Republicans is shrinking, the number of moderate Republicans who get elected to office is not shrinking. I see them continuing to run in the major urban states where we've made our reputation. We've won more than 75 percent of all the races. That's why we're still around. This is a very unforgiving business. The mortality rate is high."

Some political observers feel, however, that Deardourff does not adequately gauge the inner workings of the Republican Party and, for example, totally misgauged Ronald Reagan's 1976 popularity.

Deardourff has trouble with the right-wing pull of the Republican Party because it truly is foreign to him. He says it is a mistake for the party to the itself to something as "inherently flaky and unproven as the Roth-Kemp bill." He glumly surveys the 1980 Republican presidential hopefuls landscape and sees it populated.

So who will he be working for in 1980? "I don't know. I'll have to start thinking about that soon after this election."

But first, it's Caracas, Venezuela, where Deardourff is vying with other American consultant heavies - David Garth, Joe Napolitan, Robert Squler, F. Clifton White, pollster Patricks H. Caddell, Matt Reese. A 10-way race for president will be decided there in December.

Deardourff's piece of the action is a third-party candidate named Diego Arria. With a grin, Deardourff says that "our international chances for consulting are limited in other countries there is a certain absence of free elections." Venezuelan petrobucks have led, however, to an "incredible expansion of TV use in politics there." As in America, "Advertising now nominates a portion of Venezuelan political life."

After Venezuela, Deardourff says he will allow himself some of the quiet pleasures of the leaner, non-lucrative off-election years - being with his wife and daughter, teaching, playing golf "alone" and "getting away from people."

Deardourff's cool belies the gambling instinct that lurks inside a political consultant. As he admits, "I don't have any of the kind of drive for your security. I understand completely in this business that winning is all important.

"But one of the strengths in this business is that I am basically very controlled . . . I . . . don't . . . It's both a strength and a weakness, I suppose I don't have big highs or lows. A lot of people who work with me or with whom I am working are manic at this time of year. I think it's important to be able to stand back a little bit. To react on an intellectual level - rather than a high-pitched emotional level."

At one point in the long election night, Betsy says Deardourff is giving some thought to "reassessing this work, to see if there are not other ways to do it." He was gone 255 days this year. In October he was home one day - "and carved Megan's pumpkins. It was a special effort to be here."

For the moment, however, the wins are enough to carry him on a real high. "It'll take him until Christmas to calm down," says Betsy - "and for me to figure out that he doesn't eat when the baby eats."

Tomorrow it will be a long postponed trip to the dentist. But Deardourff had once again accomplished a record in business where the only standard is winning.

"Let's see . . . ending up with governors in Ohio, Michigan, Pennsylvania, Illinois and Iowa . . . you've got a band of guys who give the moderate Republicans at least a toe-hold in some of the larger electoral states . . . They may support a candidate for national office . . ."

When Deardourff put it that way shortly after midnight on elections night 1978, then 1980 seemed near.