The scene opens with a close-up of a lone horseman, his sturdy hulk rocking gently in the saddle as his determined mount slowly climbs a rocky trail through dew-laden pines. The camera recedes to reveal the solitary traveler nearing the summit of a mountain ridge. In the valley below, the viewer beholds a sweeping vista of farms and country roads bathed in the golden glow of a rising sun.

"There's a whole new spirit in this country today," intones a melodious, masculine-voiced narrator. "It's called getting back to basics, getting back to hard work, getting back to the real freedom of the free enterprise system. This is a Reagan idea, and it's an idea whose time has come. But . . ."

And here the steady and assured narrator makes his point " . . . we in Virginia have been saying this for a long time. You see, America is starting to do things the Virginia way. And that's the way we're going to keep them."

That is how Robert Goodman, sititng in his Baltimore consulting office, imagines the first of Marshall Coleman's television advertisements should look. Goodman, the image-maker who sold Maryland on Spiro Agnew, is known in his trade as the creator of some of the most dramatic, some would say emotional, political ads ever made. It was Goodman, after all, who once tried to dramatize government overregulation in a western U.S. Senate campaign by showing a cowboy riding off to the plains carrying a federally required port-a-potty behind him.

His imaginary ad for Coleman might seem like just a fluffy collection of pretty pictures and pretty words. But it was calculated to accomplish several things simultaneously in overcoming what many perceive to be Coleman's image as too young and ambitious.

There are two reasons, for example, why Goodman would use Coleman as the narrator of his first series of ads, but not put his mug on the screen, instead of using an actor as the solitary rider. First reason: Coleman's good looks might aggravate his problem of youth in a state so drenched in elderly wisdom and history.

Second reason: "It's really the vulnerability of candidates that reaches other human beings," says Goodman. "So being vulnerable is good. And being not so handsome is good. Sometimes being too handsome can be a terrible thing because we can't get the people's attention off the 'bod' and into the mind."

The next thing Goodman's imaginary ad would attempt to accomplish is to link Coleman to what he sees as the country's embrace of Virginia-style values in electing Ronald Reagan. Explains Goodman: "Mr. Coleman has to show that he has the credentials, the maturity, that he's right in line with what's happening and he's going to make it better. He needs a sense of mission."

So we hear Marshall Coleman giving what amount of history lectures and extolling the accomplishments of his Republican predecessors. We see broad vistas of the Virginia landscape and its many monuments.

"He could make Virginia proud that the nation has taken the Virginia idea," says Goodman. "He could use national political history, that out of Virginia tradition came a way of life that for years the country turned its back on and now is coming back to. Things that talked about Virginia and the nation as opposed to Marshall Coleman and his lust for the governorship.

"All these things would remove him from the path of those assaults. It would be very believable, very reassuring and he really would compensate for the problem of youth. And it would make beautiful television."

The flipside of Coleman's image as too young and ambitious is his reputation as a closet liberal in a state where most politicians attempt to out-conserve one another. Coleman has already experienced some troubles with this part of his image: he so far has been unable to gain the endorsement of former Gov. Mills E. Godwin, one of the party's kingmakers whose legacy Coleman is supposed to be inheriting.

Dealing with this problem may be even harder for Coleman than changing his ambitious image, and it will be particularly difficult because his opponent, Charles S. Robb, is rather conservative himself. Will the public buy a new Marshall Coleman suddenly abandoning some progressive causes to better fit the mold of Godwin-Dalton legacy? Goodman thinks it can be done. b

"For every characteristic, there's an equal and opposite interpretation," says Goodman. "I think I'd be very up front with it. I'd say: 'Damn right, I felt this way, but then I started to consider this and this.' There's nothing wrong with changing your mind. I think if the thing were done skillfully, it would show another side [of Coleman], rather than saying the whole animal has changed its spots."

In his second wave of television advertisements, Goodman would bring Coleman down from the mountains to mingle in the valley with the people and, occasionally, with John Dalton, George Bush and Ronald Reagan. These ads would attempt to show Coleman not as an opportunist, but as someone who cares. They would show Coleman surrounded by his loyal constituents, working on the roads, in factories, at picnics.

"He goes up the mountain, comes down from the mountain. The people embrace their leader," Goodman says. "That's nice."

Finally, Goodman would place Coleman behind his desk in the attorney general's office, outlining his program for the governorship and looking very mature, unaggressive, not about to change things too much. "Mr. Coleman probably should be hesitant thinking of doing many dynamic things," concludes Goodman. "A guy has to look safe. Governors are more like father figures or like a nice uncle who always remembers you on your birthday. People don't want their governors to make waves. They also don't want them to be stupid."