As Michelle Obama continues her "make-over" tour, jumping from an appearance on The View's coffee klatch to the cover of glossy Us Weekly (story title: "Why Barack Loves Her"), it's clear that we haven't really progressed much in the past two decades. Educated, outspoken, potential first-ladies frighten Americans today as much as they did when "scary feminist" Hillary Rodham Clinton first blazed the path from the corner office to the campaign trail.

Voters are suspicious of influential spouses—period (think Eleanor Roosevelt or Bill Clinton during the primaries). Still, every election is different and this one has the special spice of race. Though Barack Obama is the first black candidate on a major party ticket, he has one advantage that his wife does not—he's the bi-racial son of an African immigrant, while she is the daughter of African-American parents descended from slaves. And research demonstrates that white people tend to favor black immigrants over African Americans whose ancestors have been here for hundreds of years.

Prominent researchers like Nancy Foner, George Fredrickson, and Mary Waters, who study the integration patterns of black immigrants, have observed that white people seem more at ease with black immigrants than they do with other African Americans. Their research notes that black immigrants are usually described as "more polite, less hostile, more solicitous, and easier to get along with." Some of this is likely due to real cultural or socioeconomic differences (for example, Africans who immigrate to the U.S. tend to be highly educated, on average). However, there's no getting around the fact that we live in a country with a profound history of racial turmoil and that prejudice against African Americans persists in contemporary society.

The "preference" for black immigrants over other African Americans is perhaps most pronounced on our nation's prestigious college campuses, where a controversial debate has erupted about the overrepresentation of black students from immigrant backgrounds (as opposed to those whose ancestors have been here for hundreds of years). In the February 2007 issue of the American Journal of Education, researchers at Princeton and the University of Pennsylvania published findings from surveys given to 1,051 black freshmen at 28 selective colleges. They found that 27 percent of African-American students were first or second generation immigrants, which is more than double the national average for all blacks ages 18-19. The percentage of immigrants was even more pronounced at the four Ivy League schools included in this study (Princeton, Yale, Columbia and the University of Pennsylvania), where 41 percent of students were first or second generation immigrants. These numbers do not include international students who identify as black.

Why are black immigrants so overrepresented on selective campuses? While it's true that black immigrants are more likely to have higher grades and test scores (as I noted, their parents tend to be more educated), the authors of the study also conclude that admissions officers may be subconsciously selecting applicants with the "sociable qualities" that they more readily perceive in immigrants over other African-American students. We can't be certain of the degree to which this bias may play a role in college admissions decisions, but it's also hard to ignore previous research that demonstrates that white people find black immigrants more "likeable."

In researching my book, Fat Envelope Frenzy, I followed five different students navigating the selective college admissions process. One of the students was Ethiopian-American, grappling with the implications of his heritage on affirmative action policies. He often talked about how he couldn't relate to the other African-American students at his Memphis high school, but he also emphasized that he didn't think that race was such a big deal. "When was the last time someone was awarded a Nobel Prize because of their race?" he once asked me, rhetorically.

If only it were that simple. It would be nice if science was objective, but the ugly truth is that scientists have contributed to racism, sexism, anti-Semitism, and every other possible prejudice throughout history. Sure, no one is given a Nobel Prize simply because they are white, black or brown. But that didn't stop James Watson, who won the Nobel for his work on DNA, from claiming that black people are "less intelligent" than white people just last year.

Though Barack Obama has suffered his fair share of background-based biased attacks (He's a Muslim! He hates Jews! He'll let Iran nuke Israel!), until the Jeremiah Wright hullabaloo, he was thought of as "not black" or "not black enough." Even with her two Ivy League degrees and Jackie O hair-do, there was never that kind of debate over Michelle's racial identity. The barely restrained racism directed at her in the press is practically old news, from the covert conspiracy theories of "respectable" writers like Christopher Hitchens—who basically blamed Michelle for the Wright controversy because she wrote her 1985 Princeton undergraduate thesis about "Princeton Educated Blacks and the Black Community"—to the total tackiness of Fox News referring to her as Barack's "baby mama."

With her South Side upbringing and dark complexion, Michelle is "black enough"—unlike her husband—and maybe that's part of the reason that she isn't as popular.