IN JANUARY 2007, Rush Limbaugh proclaimed that "the media are in the midst of Obamagasm. Because Obama - that would be Barack Hussein Obama - has announced the perfunctory predictable exploratory committee."

Nearly 20 years ago, many conservatives blasted CBS anchor Dan Rather for referring to the then-vice president as "J. Danforth Quayle." They argued that the moniker was meant to paint Quayle as Upper-Class Twit of the Year. "Hussein" tars with a different brush, of course: "He's a Muslim - not a real American!" And there's also this fact: Americans have rarely elected, even nominated, a presidential candidate with an unusual name.

Run down the names of the 42 men who have held the office: From Washington to Madison to Grant, Wilson to Clinton to Bush, the names ring with echoes of Scotch-Irish, Dutch or German ancestry. Only one bore a name that could fairly be called unusual: Eisenhower, our only four-syllable president.

Run down the candidates who ran and lost, and the story is much the same: Scott and Colfax, Greeley and Davis, Cox and Dewey, Mondale and Kerry. One odd name jumps out: Dukakis.

That hardly went unnoticed. Comedian Pat Paulsen observed that the name of the '88 Democratic nominee looked like the bottom line on an eye chart.

Some vice-presidential candidates have found their names a target. In 1964, GOP nominee Barry Goldwater made frequent reference to "Hubert Horatio Humphrey." In reply, HHH gave a "stern" warning to Goldwater, noting that millions of Americans were afflicted by unwelcome middle names, and that Goldwater could find himself victim of a "midlash" (as opposed to backlash, then in vogue as a term for racial resentment).

Years later, during his 1980 acceptance speech, President Jimmy Carter paid tribute to the deceased liberal icon by calling him "Hubert Horatio Hornblower . . . Humphrey!" (Call it a portent.)

So it's too simple to say that what we're talking about is bigotry. Some names just lend themselves to making fun. But there are also names that evoke one of humankind's oldest instincts: the fear of strangers. Once upon a time, this hard-wired instinct made sense. Who knew what dangers were posed by someone from another clan, another tribe, who spoke in a different tongue?

Today, when many of us have been exposed to a wide range of people, there are clear signs that political xenophobia has lessened. There are, for example, 13 Jews in the Senate, while Jews make up about 1.4 percent of the population. And the Jewish senators don't come only from the likeliest states. Four of the six senators from the upper Midwest are Jews, including both from Wisconsin (Jewish population, 0.5 percent).

ON THE other hand, there's unfamiliar - and then there's really unfamiliar, plus bad connotations. In his 2004 convention speech, Obama referred to himself as a "skinny kid with a funny name," and has joked about people calling him everything from "Osama" to "yo mama." There's the oddity of his name to white Americans, and its similarity to both a murderous dictator and the most wanted terrorist in the world.

That this is too tempting for his political opponents to resist is not, I think, a matter of appealing to racism nearly as much as an attempt to reinforce the slogan Jesse Helms delivered in defeating candidate Nick Galifianakis for the Senate in 1972: "Vote for Helms - he's one of us!" If Colin Powell had decided to run for president in 1996, that message would have been much harder to communicate.

Can Obama play the game, too? Well, he might try recruiting some of America's best-known athletes. Maybe make a campaign ad with Hakeem Olajuwon, both Kareem Abdul-Jabbars (the ex-L.A. Laker and the Miami Dolphin) and Muhammad Ali. Either that or change his first name back to Barry, put an apostrophe after the "O" and go all out for the Irish vote. *

Jeff Greenfield is the senior political correspondent for CBS News. This first appeared in Slate (www.slate.com).