The national political world discovered a young Illinois state senator from Chicago in 2004, when Barack Obama stole the show at the Democratic National Convention with a speech of stirring eloquence. Now, just four years later and midway in his first U.S. Senate term, Obama finds himself the front-runner in the race for the Democratic presidential nomination.

In recent days, he's also found himself atop the fiercest bucking bronco of a controversy thus far in the campaign. Comments from Obama's minister, the Rev. Jeremiah Wright, recently retired from Trinity United Church of Christ on Chicago's South Side, have come to sting the candidate who says Wright led him to Christ, married him and baptized his children.

In sermons, including one after 9/11, Wright has said American policies were "chickens coming home to roost" and has described the country, so far as its treatment of black citizens goes, as murderous.

Tuesday, Obama turned a test of his own resilience as a candidate into what could be the beginning of a dialogue on a subject most politicians try to avoid -- the racial divide in this country. Democrats have been proud of their support for civil rights, of course, and have enjoyed overwhelming support from black voters for decades. The "black vote" has typically been part of Democrats' strategizing, although black leaders on occasion have felt that support was taken for granted.

Republicans, while rarely enjoying much African-American support, have made overtures to black leaders -- but they've also played on class differences to appeal to a conservative base. That pattern on the part of both parties has been predictable for a very long time.

But few politicians have been willing to immerse themselves in a real discussion of lingering racial division.

Obama, the son of a black father from Kenya and a white mother from Kansas, made a somber but meaningful speech at the National Constitution Center in Philadelphia, and underlined a truth that holds no matter what the party or the candidate: that the country must "move beyond our old racial wounds" to address problems common to all people.

Two examples of the need for that unity are prominent in this campaign. The war in Iraq is color-blind in its fury, and in the sacrifices it has demanded of soldiers of all races. The economic crisis linked to the collapse of the housing and credit markets has taken a toll in jobs and fear on the poor and the middle class.

Obama rightly rejected the angry rhetoric of Wright, while noting that Wright has worked to better the lives of those in his community, served as a Marine, and suffered the cruelties of the Jim Crow era.

The senator viewed the lack of dialogue and understanding between black and white in this way: "It's a racial stalemate we've been stuck in for years. ...But I have asserted a firm conviction, a conviction rooted in my faith in God and my faith in the American people, that working together we can move beyond some of our old racial wounds and that, in fact, we have no choice -- we have no choice if we are in fact to move toward a more perfect union."

Obama's speech was political, certainly. He needed to heal some wounds of his own. But if he has "cracked the code" on discussing, and ultimately trying to deal with, the issues of race that have divided this country since its founding, he can be said to have run a constructive race for the presidency, win or lose.