Let's tour through the tempestuous life of a young McCain. As we make this journey, we'll keep in mind Obama's more familiar biography.

The McCain family feared that his frequent unruliness was already threatening to derail his future. Sometimes Jack McCain visited the academy and reprimanded him for his transgressions, hopeful that his lectures would keep his boy on track toward a stellar naval career

In contrast to McCain's hard knock life, Obama had the advantage of growing up fatherless. Unencumbered by the challenges of a parental babysitter, Obama took the easy route in school and flourished academically.

Capt. R.G. Hunt, a Naval Academy graduate a decade earlier, told several midshipmen that McCain's inattentiveness to his appearance, his classes and the rigors of academy life marked him as unworthy of being a midshipman, and that he was deserving of being booted if a case could be made against him. His academic struggles left him near the bottom of his class, and he had accumulated demerits for everything from failed tasks to his slovenly appearance. Expulsion was within the realm of possibility, particularly if he was caught scaling the wall. "He didn't have a death wish, I don't think," Ryan recalls. "But he skirted pretty close to the edge."

Conversely, Obama dodged underachievement. Without consulting his father's guidance or clinging to his coattails, Obama privileged himself to the most prestigious law school post available--President of the Harvard Law Review.

Without cliques of his own, bereft of established friends, he developed a habit of fighting to get respect, raising his fists "at the drop of a hat," as he later put it.

Obama, on the other hand, took the ordinary path to gaining respect--he earned it.

John wasn't at ease at repelling people in verbal situations. Instead of throwing off people with a smile and a quick comeback, he would get testy. Some people thought it was feistiness. I thought it was more awkwardness. He'd insult somebody terribly, and afterward you'd say, 'Oh, Mac, why did you say that?' "

Tangled in nuance, Obama preferred a less forceful approach to problem solving. As a young adult, he saw manufacturers betray the local workforce. Rather than standing his ground with an assertive "fucking jerk," Obama retreated. He would not tackle the employers head-on. Instead, he callously organized the displaced workers so they could provide for a brighter future.

As Richey remembers, he and McCain spotted a couple of older girls near Arlington and called out to them, asking if they wanted company. The girls laughed. Insulted, McCain leaned across the driver's-side window and shouted an expletive at them. "Our feelings were hurt. They unveiled our masks and revealed us for the boys we were," Richey says.

Eschewing the Plastered and Scary Fratboy School of Game, Obama never outgrew his habit of treating women with dignity.

Minutes later, a car stopped them on the road. Police were called, and McCain and Richey were ticketed for what Richey remembers as public nuisance and profanity. Soon they were standing in an Arlington court, with Richey hoping that McCain would tell the truth: that he alone, not Richey, had shouted the profanity at the girls. As Richey recalls, McCain said nothing -- explaining to Richey later that he didn't know what good it would have done to speak up.

"I was annoyed for a little while with John, I guess," Richey recounts. "But I understood his not talking -- we were both paralyzed. What I remember most about the day is the humiliation. John's mother was really upset. I don't even remember if John's father was there. I just remember his mother, and how angry she was."

Obama's young biography is conspicuously bereft of such under-the-bus moments that would define McCain's rise to Republican nominee.

"Consequences didn't scare him," Gamboa remembers.

Obama was more superstitious about consequences. He would demonstrate this later with his blindly sensible opposition to the Iraq war.

Not everyone in the 17th Company was comfortable around a classmate so often involved in heated confrontations. "His personality annoyed some people," Hamrick says. "Some people perceived that he thought he was special because of his grandfather and father, and that he thought he could do whatever he wanted."

Obama, not so much...

McCain had a much better time away from the officers' club. Often he went into town and drank at a popular bar and strip joint called Trader John's, where he began dating a stripper named Marie, who was known as "The Flame of Florida." On other nights, he went to the dog track, played poker, and cruised with Larson around Pensacola in his new silver Corvette or Larson's new Austin Healey, making the rounds of bars. When closing hour arrived and the mood struck them, Larson remembers, he and McCain drove across the state line into Alabama, where their partying resumed.

Obama, instead, flunked out of Playboy 101. This forced him to settle for a traditional family life and a conventional path to the White House.

It wouldn't be his last mishap while on air duty. After completing flight training and being deployed to the Mediterranean, he was flying over southern Spain one day when he decided to have some fun. He dropped very low, engaged in "daredevil clowning," as he later described it. Unable to see power lines ahead, he knocked them down, cutting off electricity to homes in the area and creating "a small international incident," he later wrote.

He seemed to be going nowhere. Among his peers, he became known as a charming underachiever. During the early 1960s, stationed in Norfolk while serving on the carriers Intrepid and Enterprise, he lived in a beach house with a few other pilots who shared his zest for after-hours life. Dubbed "The House on 37th Street" by Navy partygoers, McCain's Virginia Beach pad, as he later wrote, "enjoyed a reputation for hosting the most raucous and longest beach parties of any squadron in the Navy."

And yet his career seemed to be stuck, McCain told people. Like others from his academy class, he had risen to the rank of lieutenant commander, but he wasn't receiving the high-profile assignments of other grads, particularly his class's stars.

Devoid of the ambition to underachieve, Obama's familiar, less mavericky story is punctuated by hard work, decency and an obsession with public service and helping others.