Seventeen years ago, in the midst of the Vietnam war, Albert Gore Jr. appeared with his father in a television commercial aimed at dramatizing the two-fisted patriotism of the elder Gore, who was fighting a losing campaign for reelection to the Senate from Tennessee.

The father rode onto the screen on a white horse; the son wore his brand-new Army uniform. It was state-of-the-art imagery politics for its time, all the more striking because both Gores were adamant foes of the war.

Thirteen years later, the younger Gore, who had followed his father to Congress and was by then in his fourth term in the House, embarked with several colleagues on an effort to work out a compromise with the Reagan administration that would further the cause of arms control.

They got their compromise, and it helped established Gore as an innovator on arms control, a full-fledged member of the nuclear-strategy club. But it also assured a new lease on life for the controversial MX missile, angering many liberal colleagues who accused Gore of naivete' or worse. "A triumph of hope over achievement," said Rep. Barney Frank (D-Mass.), a friendly critic.

Now Gore, who moved to the Senate in 1985, is running for the Democratic presidential nomination both as a tested champion of arms control and, more recently, as the candidate with the most hawk-like position on national defense issues.

Contradictory as its central themes may appear, the Gore platform -- "War and Peace for the '90s," as a congressional colleague wryly described it -- flows quite naturally out of the personality and record of this self-styled "raging moderate."

He has a record on defense as well as domestic issues that parallels those of his leading rivals for the Democratic nomination, falling in the liberal-to-moderate area in most rankings of congressional votes. He voted, for instance, for a nuclear freeze, for reductions in President Reagan's military budget, for limits on the administration's "Star Wars" missile defense program and against military aid to the Nicaraguan contras.

But as he seeks to separate himself from his competitors and emerge as the leading contender in the "Super Tuesday" southern primaries and caucuses next March, he can -- and does -- point to major distinctions that give his record a more conservative cast, especially in the national security area. He cites his support of the U.S. tanker-escort operation in the Persian Gulf, along with the earlier invasion of Grenada and the bombing of Libya. He opposes one of the latest aims of the peace movement, a ban on missile flight tests. And, unlike his rivals, he supported $3.5 million in nonmilitary aid to the contras during the Central American peace effort this fall.

As a whole, Gore's 11-year record in Congress is as smooth and polished as the candidate, who attempts to portray himself as the embodiment of a youthful new Democratic Party without the old rough edges and fault lines.

He is the political image-maker's dream come true: good looks, good pedigree, good re'sume' without a hint of scandal. The only brush he has had with such trouble was his admission last week that he had smoked marijuana long before he held public office.

Ambitious but well-mannered about it, religious but not overly so, he is said to be bright, earnest, articulate and courtly for one so young. The father of four, he is married to his high-school sweetheart, who has said her efforts to fight obscenity in rock music lyrics will continue despite the Gores' recent effort to mend fences with the music industry. His tours of duty included Harvard, Vietnam and divinity school as well as a brief career in journalism. He's done a little land-developing, qualifying him as a businessman. He's a farmer, too, with a prize herd of black Angus cattle.

At 39, he is the youngest candidate in the race to succeed the oldest president. The accent is southern, the breeding is St. Albans, the exclusive preparatory school here that he attended while his father served in the Senate.

His approach is cerebral, analytical, cautious -- as typical of the emerging new breed of Democratic leaders as his father's more romantic, passionate liberalism was a hallmark of his generation.

The younger Gore does not reject the old theology; he simply looks around it, through it and beyond it. "He tends to distrust ideological views of the world. They do not seem to work for him," said Martin Peretz, editor of The New Republic, who taught Gore in college and whose magazine has found much to admire in him now.

Gore rejects "litmus tests," talking instead of "pragmatic" solutions to today's problems, as well as "visionary" responses to problems of the future. He has devoted countless hours and words in hearings, speeches and studies to subjects from biomedical research and genetic engineering to the "greenhouse effect" and holes in the ozone layer. He is a candidate of the high-tech generation, one of the "Atari Democrats" who so baffled old pols like former House speaker Thomas P. (Tip) O'Neill Jr. (D-Mass.).

His futuristic preoccupations have contributed to his reputation as a serious, forward-looking lawmaker and kept him out of the ideological mud fights that have smudged less artful politicians. But they have also led to suggestions that he is overly cautious and calculating, disparaging litmus tests because he would flunk them.

Gore has a populist streak -- and a flare for drawing attention to his causes -- that is reminiscent of the elder Gore. But it is a populism that has been updated for the 1980s, focusing on corporate and governmental excesses in areas stretching from infant formulas to contact lenses, from the dumping of hazardous wastes to safety problems on NASA projects.

"What is most characteristic of Gore is that he takes a highly technical issue, masters it and promotes it with a view toward maximizing its potential for media attention," said Ann Lewis, a liberal Democratic activist and former executive director of Americans for Democratic Action.

"I don't think it's artificial. It's strategic," she added. "Like most candidates these days, you don't see a lot of emotion, a lot of traditional Democratic rhetoric. He doesn't run against government or the Democratic constituencies. But he picks and chooses his issues carefully."

"Al's a calculator, not a chance-taker," said a former House colleague who opposed Gore on the MX and other arms issues. "Al has a single-minded desire to be an achiever in whatever he gets involved with . . . . His eye is squarely on the brass ring," said Sen. James R. Sasser (D-Tenn.), a longtime family friend as well as political ally.

Asked if his son has ever failed at anything, Gore Sr. paused and then said, "No, not that I know of. He chooses his goals and then achieves them."

Gore's wife, Tipper, makes essentially the same point. "He would always set his sights after something and go after it 100 percent," she said.

It is the intensity of Gore's drive to achieve -- to excel at whatever he does -- that has struck many of his colleagues as his greatest strength as well as a potential liability.

"He seems in such a hurry, so intense about everything. It can set people's teeth on edge," said one colleague. Said another: "He's not arrogant, but I certainly wouldn't call him humble." Yet another said he "naturally inspires envy because he's so damn good at whatever he does."

When colleagues are asked what they think of Gore, most speak of his intelligence, drive and methodical capacity for work. A smaller number, his inner circle of friends from the House, have found an engaging sense of humor and personal warmth rarely revealed in public.

"I've been in the House for 19 years and I can say I've never seen a more intelligent member. He's got enormous drive and conviction but he can laugh and relax, too," said Rep. Norman D. Dicks (D-Wash.), a close friend and supporter.

In the Senate, only Gore's home-state colleague, Sasser, could be described as a close friend. "Al always wants to lead . . . and that can create some resentments," said Rep. Thomas J. Downey (D-N.Y.). "It may be that he's more appropriately a president than a legislator."

Sen. David H. Pryor (D-Ark.) remembers a lull in a meeting of the Senate Rules Committee shortly before a congressional recess. As Pryor and others relaxed, Gore, flanked by several aides, pored over a huge map of Tennessee marked with small flags designating locations of town hall meetings he planned to hold during the recess. "There were eight or nine meetings in a day," Pryor said. "I can do two or three, and that's pretty good. But . . . eight or nine? I almost fell over from exhaustion just looking at it."

Pryor's reaction might have been more acute if he had known that, by then, Gore was approaching his 2,000th Tennessee town hall meeting, an average of about four a week since he was elected to the House.

Gore is showing the same intensity in his presidential drive. Winding up a grueling Saturday of speech-making and handshaking in near 100-degree heat in southeast Iowa last August, Gore studied his Sunday schedule, which began with an 8:30 a.m. breakfast, and scowled. "Can't we find a factory to visit before that?" he asked. "On Sunday?" an aide asked incredulously. "There's got to be one somewhere," Gore insisted.

Gore's burst onto the national stage with the MX-arms control compromise of 1983 offers some insight into his credentials for a presidential bid, revealing both strengths and weaknesses, according to partisans on both sides of the issue.

It began with an unlikely event during Gore's fourth year in the House: an appearance before a Girls' State meeting in Murfreesboro, Tenn., in the summer of 1980.

Gore had sensed a rising concern about nuclear war among his constituents but was shocked with the response when he asked the girls whether they thought there would be nuclear war in their lifetime. Most raised their hands. Then he asked, "How many believe we can change that if we really try." He was appalled when only three or four raised their hands.

When he got back to Washington, he embarked on what amounted to a year-long crash course on arms control. He sought and won appointment to the House intelligence committee and devoted eight hours a week for 13 months to detailed study of the subject, reading under the guidance of experts and calling in specialists for private briefings.

What he hoped to do was to "develop a theory of understanding the arms race, different from the way anyone else was talking about it." By March 1982, he unveiled it in an hour-long speech on the House floor that was ignored at the time by most of his colleagues -- but not by the Soviets.

Among the few requests for copies was one from the Soviet Embassy, starting a chain of events that catapulted Gore into national, even international, prominence. Within a couple of weeks, an American delegation led by Minneapolis Mayor Donald Fraser visited Moscow and was peppered with questions about the "Gore plan." They brought back word of the Soviet interest and within months it had become the hot new idea for arms control and was embraced by the Reagan-appointed Scowcroft commission that was studying an MX compromise.

The idea was to move from multiwarhead (MIRV) missiles to single warheads on mobile launchers (Midgetman missiles), making it more difficult for one side to make a first strike that would knock out the capacity of the other to retaliate. In theory, it could take the entire arsenal of one side to knock out only part of the other's supply of weapons, thus deterring a first strike by exposing the attacker to devastation by the country that was attacked. The underlying idea was to put the attacked country in a better position than the attacker, thus convincing leaders on both sides never to contemplate launching a deliberate attack.

The Reagan administration adopted Gore's concept as one option for future strategic policy in a deal it subsequently negotiated with Gore and several other House Democratic moderates, including Rep. Les Aspin (D-Wis.), now chairman of the House Armed Services Committee. The deal assured deployment of a limited number of MX missiles in exchange for development of the Midgetman and new steps toward a broad arms-control agreement with the Soviets.

But with the MX in hand, the administration remained cool to the Midgetman, offering at one point to eliminate the program as part of a broader deal with the Soviets. "The Midgetman is going only as far as Congress can force," said one congressional arms-control expert. Gore continues to see it as a linchpin of arms-control strategy for the Democrats and his concept has retained respect in the arms-control community, although Gore's enthusiasm is not universally shared, especially in more liberal quarters of the party.

In some respects, the episode summed up the arguments for and against Gore. It showed he was bright, creative, hard-working, skillful in deal-making, even a bit bold in challenging liberal dogma of his party. But critics say it smacked of calculated self-promotion, aimed at furthering his image as a defense intellectual with a muscular approach to arms control, along with gullibility in trying to cut a deal with Reagan on arms control.

"The question is whether it has done as much for arms control as it did for Gore's career," said one colleague.

Although Gore was born in Washington while his father was well into his congressional career, the family's roots are in the small (pop. 2,700) town of Carthage, Tenn., in the Cumberland foothill country between Knoxville and Nashville, where both Gores still maintain homes and farms.

But the younger Gore's upbringing was a far cry from that of his father, whose formal education ranged from a one-room schoolhouse in Possum Hollow to night law school at the YMCA in Nashville.

Although Gore Jr. spent summers and holidays in Tennessee, he attended school in Washington, including the exclusive St. Albans School for Boys on the grounds of the Washington Cathedral, where he was an honors student as well as captain of the football team.

Living with his parents in an apartment at the old Fairfax Hotel (now the Ritz-Carlton) on Embassy Row, he was raised on government and politics, including dinner-table conversations that often included friends of his father from Capitol Hill. His mother, like his father, was a lawyer and intensely interested in Washington public affairs, a "formidable personality in her own right," said an admiring friend of the family. Gore accompanied his father on political trips, even abroad. As a teen-ager, he served as a translator for his father on a trip to Central America.

The family was exceptionally close-knit and supportive of the younger Gore's aspirations, according to friends, although Gore says they never tried to push him into politics.

His wife-to-be, Mary Elizabeth Aitcheson, known as Tipper, recalls being struck immediately that "here was someone different" when she met him at a St. Albans dance during Gore's senior year. "He had such a serious outlook toward life, always talking about issues and the future," she said. "Most 17-year-olds just don't talk about those things."

Gore went from St. Albans to Harvard University, where he studied English in hopes of becoming a writer but switched to government studies after a grim encounter with Chaucer. He wrote his 100-plus-page senior thesis on the impact of television on the presidency from 1947 to 1969, and it drew considerable acclaim. He graduated cum laude in 1969.

Gore's four years at Harvard spanned some of the most turbulent years of the Vietnam-era campus protests. Peretz, who taught a course on social theory that Gore took while at Harvard, has described him as "a gentleman at a time when there were very few gentlemen left on campus." Peretz recalls inviting Gore's class to dinner one night. When Peretz's wife walked in, "here was this freshman standing up and saying 'Hello, ma'am.' She looked around to see if some old woman was standing behind her. You just didn't hear that kind of thing from freshmen at Harvard in 1966 or 1967," he said.

"He was always against the war, but violence was out," said Tipper Gore, who married Gore after completing her senior year at Boston College in 1970. The senator recalls attending antiwar rallies. "If you call that demonstrating, I demonstrated," he said. But "more aggressive" involvement was not the Gore style. "I remember going to a meeting where somebody proposed to destroy a railroad switching point with explosives. I said, 'Wait a minute, whoa, that's crazy . . . . I don't want to hear any more about that.' "

After graduation came the choice that so many well-educated, affluent young men faced at the time: whether to serve in Vietnam. "I knew there were plenty of ways to get out of it, and I certainly considered them," he said recently. His parents were prepared to stand behind him -- whichever choice he made. His mother told him that if he wanted to go to Canada, she would go with him.

"The main reason I decided to go was that I came from a small town of 2,000 people. If I didn't go, one of my friends would have to go," Gore said. "I felt I had a duty to serve; it was that simple."

There was another concern: his father. A conservative tide was running against the elder Gore, whose liberal stands on national issues were beginning to take a toll at home. He was one of few southerners who refused to sign the "Southern Manifesto" against school desegregation in the 1950s and continued to defy conservative sensitivities with outspoken opposition to the Vietnam war in the 1960s. Under challenge from William E. Brock III, a young candy-fortune heir who was calling him "the third senator from Massachusetts," Gore Sr. was facing the most difficult fight of his 32-year career in Washington -- a fight he eventually lost.

With his father's patriotism under fire, Gore knew how difficult it would be to have a draft resister in the family. "It was not the cause of my decision but it did make it easier to analyze the other elements of the decision," Gore recalled.

Gore enlisted in the Army and went to flight-training school at Fort Rucker, Ala., bound for Vietnam. It was at this point that he appeared in the man-on-white-horse television spot that concluded with Gore Sr. reaching out, touching the hand of Gore Jr. and saying, "Son, always love your country."

Gore spent his six months in Vietnam as an Army journalist, assigned to an engineering brigade outside Saigon. He saw combat but never fought in it. He sent some of his articles home and they were reprinted in the Nashville Tennessean, where Gore turned for a job when he returned home and worked until he ran for the House five years later.

Along the way, from Harvard through Vietnam and into his early reporting career in Nashville, Gore had soured on politics.

"When I was a young child, my father was a hero to me; he still is. I felt politics was something I might be interested in. But then I became disillusioned with the entire process, mainly because of the country's successive experiences with Vietnam and Watergate. I felt very strongly that politics would be the last thing I would want to do," he said in an interview, scowling as he talked.

But as he worked his way up from stories that could kill a budding journalism career (including one about a Whopper-eating contest at a Burger King franchise that led with news that the leading contestant threw up after three burgers), Gore began to drift back to his old interests. While on the police beat, he attended divinity school at Vanderbilt University, quitting when he was assigned to cover local government.

It was on the governmental beat, which was based largely on investigative ventures, that he learned many of the skills that shaped his career in Congress. He spent hours combing through files and documents, eventually uncovering bribe-taking on the Nashville City Council and writing a series of articles that led to the indictments of two officials and conviction of one.

"I began to think I had a talent, I could make a contribution," Gore said. "It released a source of energy I didn't know I had. There was a predisposition there all the time, I guess." While covering the corruption trials, he started attending Vanderbilt law school.

When word passed that the local congressman, Joe L. Evins, would not seek reelection in 1976, Gore was ready, announcing his candidacy the day that Evins announced his retirement. He won narrowly and returned to Washington, where he served in the House until 1984, when he ran for the seat of retiring Senate Majority Leader Howard H. Baker Jr. (R-Tenn.) and won by a landslide.

In the House, he became a virtuoso of the committee hearing, earning praise for hard work, ingenuity and perseverance, but also attracting criticism for headline-grabbing and camera-hogging. Rep. Joe Skeen (R-N.M.) and Sen. Ernest F. Hollings (D-S.C.), who shared committees with Gore, have grumbled publicly about his zest for the limelight. "That young know-it-all takes some getting used to. He hasn't paid his dues," Hollings has been quoted as saying.

As a member and then chairman of the House Science and Technology subcommittee on investigations and oversight, Gore conducted hearings on subjects from human-embryo transplants to Alzheimer's disease. He also chaired hearings of the Energy and Commerce investigations subcommittee on subjects such as nurse midwifery, the safety of soft contact-lens solutions and competition in the drug industry.

He sponsored legislation establishing a national computerized network for organ transplants, requiring stronger warning labels for cigarettes, protecting the safety of infant formulas, setting up Alzheimer's treatment centers and creating procedures to help curb medical malpractice. He was a principal sponsor of the legislation that created the Superfund for toxic-waste cleanup.

More recently, as a member of the Senate Science, Technology and Space Committee, he was credited in uncovering NASA cutbacks that may have contributed to last year's Challenger space shuttle disaster.

"He has a knack for picking issues that shows real insight into their importance . . . and he approaches everything in a very methodical way," said Sen. Harry Reid (D-Nev.), who served with Gore on House as well as Senate subcommittees. "He also knows how to get attention," Reid said.

Gore bristles at suggestions, many of them from disgruntled and sometimes envious colleagues, that he chooses only safe issues with good prospects for news media attention. "If organ transplants was such a 'motherhood' issue, why would no one else touch it with a 10-foot pole?" he asked with a rare show of anger. "It was a political minefield . . . filled with religious taboos." He earned a perch at the top of the American Medical Association's "hit list" for pushing standards on new technologies, a subject so arcane that few others bothered to notice, he said.

He likes problems "with finite answers," problems "that I can help solve," Gore said.

Some associates believe it goes beyond that, however. Earlier this year, several other Democratic senators were chatting about who among them was the most driven -- driven enough to run for president. One by one, they dismissed the names that had already been mentioned. To their surprise, they came up with a new name. It was Albert Gore Jr.