Since World War II, no two candidates have had such strikingly similar backgrounds of class and privilege, with so many points of overlap.

Excerpts from a 10-10-04 N.Y. Times article entitled "Since World War II, no two candidates have had such strikingly similar backgrounds of class and privilege, with so many points of overlap:"

[W]hy do these two guys dislike each other so much?

It is not as if they have nothing in common. Since World War II, no two candidates have had such strikingly similar backgrounds of class and privilege, with so many points of overlap. These two not only attended Yale University two years apart, but were also members of the same secret society there, Skull and Bones.

The president, according to several Republicans who expressed worry about Mr. Bush's debate performances, may have become too accustomed to deferential treatment. Mr. Kerry's advisers believe their candidate can set him off simply by confronting him.

"He's never in an environment where he's contested," Michael D. McCurry, a senior spokesman for Mr. Kerry, said of Mr. Bush.

The race is on a knife's edge, and the ideological divide between the candidates is real. But advisers to both men say that the competition is personal as well as political, and that it stems partly from the similarity of their backgrounds.

Aides to Mr. Bush said that Mr. Kerry reminded him of the Brahmins he met, and disliked, at Yale and Harvard Business School. "One word the president uses sometimes is 'haughty,' " said one person close to Mr. Bush, adding of the debate here, "and in Kerry's style, you saw some of that last night."

Stuart Stevens, a media consultant to the Bush campaign, said Mr. Kerry did not understand Mr. Bush's appeal and looked down on him. "I think he looks at him and says, 'Why am I having to go through this process when I should be president?' "

Mr. McCurry said of the clash of personalities, "It's so emblematic of the whole cultural divide" in the country.

He speculated that Mr. Bush saw in Mr. Kerry "that phalanx of New England liberals who made fun of me at Yale - who looked down on me as a frat boy."

Mr. Kerry, he said, "is very fiercely competitive and he does react emotionally. I don't know if it's so much animosity - it's just disdain for where we are in the world and how we ended up this way."

Mr. Kerry is said by his friends and associates to regard Mr. Bush as intellectually lazy and cynical.

Ticking off a list of other political rivalries, another Democratic operative who has advised Mr. Kerry noted what made this one unusual. "Johnson and Kennedy, it was class," he said, speaking on condition of anonymity because of the personal nature of the subject. "Clinton and Bush - that was class. But these guys are the same class."

Yet, he continued, within their class, Mr. Bush and Mr. Kerry filled very different, even antagonistic roles growing up. "These are guys who sat at different tables of the lunchroom," he said.

Mr. Bush was the prodigal son, Mr. Kerry the dutiful one. Mr. Bush was a prankster and a mediocre student. Mr. Kerry was earnest, idealistic, and a little lonely, a striver whose palpable ambition alienated some.

At Andover, his boarding school in Massachusetts, Mr. Bush was head cheerleader. At St. Paul's, his boarding school in New Hampshire, Mr. Kerry helped found a political club to debate current events.

Both men are of aristocratic stock. But within the elite, where subtle gradations of background take on particular force, Mr. Kerry was an insider's outsider. Unlike the Bushes, who were Protestant, the Kerrys were Catholic and they were not wealthy.

Whether he is attacking over Iraq or taxes, the common thread of Mr. Bush's critique is that Mr. Kerry has failed to make the grade in the prep-school ethos, drummed into generations of boys with Rudyard Kipling's poem "If": he lacks character. He is all ambition, no core.

And whether the subject is Iraq or taxes, Mr. Kerry's critique also boils down to a basic accusation that has dogged Mr. Bush since he was a young man: that he lacks judgment and wisdom - in a word, maturity.

In each debate, Mr. Kerry has twisted the knife by invoking Mr. Bush's father, the 41st president, implying that the son does not measure up. Call it the Oedipus hex: Mr. Kerry's aides regard it as their most effective way of undermining Mr. Bush on the subject of Iraq.

"The president's father did not go into Iraq, into Baghdad, beyond Basra," Mr. Kerry said in Coral Gables. "And the reason he didn't is he said, he wrote in his book because there was no viable exit strategy." In the same answer, Mr. Kerry noted that he had been in combat, an experience, he did not need to mention, shared by the 41st president but not his son.