Reëlections are like second marriages—a portion of the pageantry, a fraction of the idealism. The controversy now swirling around Newark Mayor Cory Booker is a reminder of that. In urging the President (and Mitt Romney) to renounce negative campaigning, Booker inadvertently offered a barometer of the difference between the Barack Obama of 2008, who strode into Washington vowing to change the tone of our politics, and the battered pol who had to produce a birth certificate to assure the public he was qualified to vote for President, let alone serve as one. Change, indeed.

But in a curious way, Booker’s comments also underscored, and possibly exacerbated, his own political problems—and not simply because his attempt to stand above the fray made him look something like a guy who refuses to help a friend in a bar fight because fighting is immature. Booker stands out in part because the public is unaccustomed to seeing black politicians do things like passionately defend private-equity funds, as he did on “Meet the Press” this past Sunday. The perception that Booker is atypical has generated a quotient of media fascination. Six years into his career, he has been the subject of a documentary (“Street Fight”), a reality series (“Brick City”), and, most recently, a book: “The New Black Politician: Cory Booker, Newark, and Post-Racial America,” by Andra Gillespie, a political scientist at Emory University. Gillespie points out that the most conspicuous assets of this new group—equal fluency in black and white settings; broad, multiracial fundraising networks; and tenuous ties to black protest politics—might also serve as liabilities as they seek higher office.

During the 2008 election season, Barack Obama was hailed as the most visible of this new class of politicians, which included Booker; Artur Davis, a congressman from Alabama; Adrian Fenty, the mayor of Washington, D.C.; and Harold Ford, a former congressman from Tennessee. Here was a group of men—and they’re all men—who would not be found bullhorning rhymes about police brutality in front of the local precinct house.

On some level, this was an arbitrary categorization: black politics has always been more complicated than simply protests and indictments of racism. But neither was it likely, in the pre-Obama era, that we might see the two of the most recognizable black politicians in the country embroiled in a flap not over affirmative action or the criminal-justice system but the contribution of private-equity funds to our economy.

Booker’s 2002 loss to Sharpe James shared so many of the undertones of Obama’s early conflict with the black political establishment as to become nearly metaphoric. When Obama struggled to gain support black support in 2007, observers recalled James’s barb against Booker: “You have to learn to be black, and we don’t have time to teach you.”

The ascent of that group did seem to mark a transition in American politics. Beyond Obama winning a higher percentage of white voters than John Kerry or Al Gore, Adrian Fenty won in all of D.C.’s wards—the traditionally black ones and the white ones—and Davis appeared for a moment to be a credible gubernatorial contender in Alabama. Booker’s breadth of support translated into not only campaign dollars but also high-profile wins like wooing Facebook founder Mark Zuckerberg, who ended up pledging a hundred million dollars to the Newark school system.

If none of those men were alumni of a police-brutality protest, they made up for it with breadth of support. As Gillespie points out, “This is the first group of black politicians who felt comfortable sacrificing some of the black vote in the belief that they would more than make up for it with white voters.”

That formula hasn’t always worked out. Of the five, only Obama and Booker remain in elected office. More disturbingly, Fenty, Davis, and Ford all lost races in which questions about their racial loyalty were at least part of the equation. In 2010, Fenty was unseated by Vincent Gray, the chairman of the D.C. City Council, whose campaign indirectly accused the Mayor of putting the interests of white D.C. residents ahead of those of his black constituents. When Davis opted to run for governor of Alabama instead of seeking reëlection to Congress, he didn’t seek the endorsement of the state’s black Democratic organizations (despite the fact that blacks make up nearly half the primary electorate), and his opposition to Obama’s health-care reform was viewed by some as an attempt to curry favor with white Alabama voters who opposed the law. He lost the primary, by thirty points, to Ron Sparks, a white agricultural commissioner. (Davis is now in Virginia, where he’s rumored to be considering a new run for Congress—as a Republican.) Ford’s 2006 senatorial campaign in Tennessee was derailed in part by an ad featuring a blonde giggling about meeting him at the Playboy mansion. On the surface this was an attempt to stir up the ancient unease about interracial dating, but beneath that was a subtle effort to discourage the most reliably Democratic voting bloc—black women—by reminding them of Ford’s catholic dating tastes. That muddled state of affairs makes it hard to know whether we’re pre-post-racial, and have something to look forward to, or post-post-racial, and largely over the whole thing. What is clear is that in politics there’s only a degree of difference between building bridges and burning them.

Nor was Booker immune to this phenomenon. He won reëlection in 2010 by a smaller margin than in 2006, and amid murmurs that he represented “outside interests” more than those of the (black) residents of Newark. Fair or not, gushing over private-equity funds doesn’t help with that perception. In that light, Booker’s most heroic accomplishments—like dashing into a burning building to save a neighbor—seemed subject to question. “People in my ward thought [the rescue] was a case of wag-the-dog,” Ras Baraka, a Newark city councilman and frequent Booker critic, told me. In the wake of the rescue the Mayor’s critics derisively began referring to him as “Story” Booker.

Booker’s warm relationship with Governor Chris Christie culminated in a Web video parodying the Mayor’s flair for heroics. The Governor, however, is less than popular with Booker’s own Newark constituents (in 2009 he lost the county in which Newark sits by forty points), and Baraka says that residents bristled at the visual of their mayor changing the Governor’s tire in the spoof. Booker’s “Meet the Press” comments reinforced his image as a new black politician, but it’s not clear that’s a good thing. “We haven’t transcended race so much that black politicians don’t need every possible black vote,” Andra Gillespie says. “Especially if you harbor higher ambitions.”

Photograph by John Moore/Getty Images.