But there are also strong reasons to believe that the Democratic nominee, at least, will be African American. First, African-Americans represent a vital voting bloc in Democratic primaries, and they — like most ethnic groups — typically rally around the favorite son or daughter. Black voters represented an overwhelming 55 percent of the vote in South Carolina in 2008, and almost 20 percent in, for instance, Florida. And the liberal white Democrats who make up the primary electorate in places like Iowa obviously have no problem voting for a black candidate.

Indeed, as Obama showed, the two great tranches of the Democratic coalition are wealthy white voters and poorer voters of color, of whom most primary voters are still black…

Third, and most important, two of the very strongest candidates for the job are black. There’s an establishment candidate, Massachusetts Governor Deval Patrick, someone who might fill a cabinet post in the second Obama term and has the classic credentials of a Democratic nominee: He’s a Harvard-educated blue state executive and former prosecutor. And there’s the Obama-esque outside star, Newark Mayor Cory Booker, already a national figure with a national fundraising network, and on a cruise course to the Senate in 2014. Both are Obama allies (which won’t hurt either), and if there was any lesson they should have taken from his 2008 run, it is: Don’t wait. Booker, in particular, is perfectly positioned to unite those two key wings of the party, should he run from the Senate.