Faced with what his advisers acknowledged was a major test to his candidacy, Senator Barack Obama sought on Monday to contain the damage from incendiary comments made by his pastor and prepared to address the issue of race more directly than at any other moment of his presidential campaign.
Though he has faced questions about controversial statements by the pastor, the Rev. Jeremiah A. Wright Jr., for more than a year, Mr. Obama is enduring intense new scrutiny now over Mr. Wright?s characterizations of the United States as fundamentally racist and the government as corrupt and murderous.
Mr. Obama, in a speech Tuesday in Philadelphia, will repeat his earlier denunciations of the minister?s words, aides said. But they said he would also use the opportunity to open a broader discussion of race, which his campaign has said throughout the contest that it wants to transcend. He will bluntly address racial divisions, one aide said, talking about the way they play out in church, in the campaign, and beyond.
Mr. Obama continued to write the speech on Monday evening, which he believes could be one of the most important of his presidential candidacy, aides said. His wife, Michelle, had not been scheduled to travel with him this week, but hastily made plans to be in Philadelphia.
Mr. Obama said Monday that in his speech, to be given at the National Constitution Center, he would ?talk a little bit about how some of these issues are perceived from within the black church community, for example, which I think views this very differently.?
After removing Mr. Wright from a religious advisory committee on his campaign on Friday, Mr. Obama concluded over the weekend that he had not sufficiently explained his association with the pastor. He told several aides he was worried that if voters did not hear directly from him ? in the setting of a major speech ? doubts and questions about him might grow.
Some associates advised him against giving the speech. ?Race is now officially on the table. It?s not going away after this,? a senior aide, speaking on condition of anonymity, recalled one adviser saying.
The episode has left Mr. Obama tending to a firestorm fed by matters no less combustible than faith, patriotism and race. It could help Senator Hillary Rodham Clinton?s campaign advance its argument that Mr. Obama is ?unvetted,? and that he is less electable than Mrs. Clinton come fall. In interviews, Republican strategists mapped out how Mr. Obama?s association with Mr. Wright could be used against him in a general election.
By addressing head-on such sensitive topics, his speech, aides and other Democrats said, could be a pivotal moment for Mr. Obama, who, for all of his electoral victories and copious news coverage, is still known only in the broadest terms by many Americans.
?This isn?t red and blue America,? said Donna Brazile, a Democratic consultant, referring to the address that catapulted Mr. Obama to prominence at the 2004 Democratic National Convention. ?This is black and white America.?
?And when you really have a serious conversation about race, people clear the room,? said Ms. Brazile, who as the manager of Al Gore?s bid for the White House in 2000 was the first black woman to run a major presidential campaign.
Mr. Obama is particularly vulnerable because voters are still getting to know him, said Democratic and Republican strategists ? and a few voters as well. The Wright affair ?makes me question other things. What else do we not know?? asked Karen Norton, 58, a computer saleswoman in North Carolina and a Republican who said that, until now, she had been stirred by Mr. Obama?s message of national reconciliation.
Mr. Wright?s statements, said strategists, threaten his greatest strength, his reputation as a unifying, uplifting figure, capable of moving the country past old labels and divisions.
?The problem is the complete contradiction between the message of the Obama campaign and the message of the minister who?s been his close friend and confidant for 20 years,? said Whit Ayres, a Republican consultant unaffiliated with any campaign.
Mr. Obama has also pitched himself as a candidate who can attract religious voters back to the Democratic Party, one who speaks the language of the Bible fluently and testifies about what he says is the impact of Christianity on his own life.
?What better way to try to undercut the way he integrates faith and political vision than to say we should all be secretly afraid of his church?? said Jim Wallis, a left-leaning evangelical who has had longstanding relationships with both Mr. Obama and Mrs. Clinton, and who says that Mr. Wright has been unfairly caricatured in recent portrayals.
In strategic terms, Mr. Wright?s statements are tricky for the Obama campaign to address. The more the candidate denounces the minister?s words, the more voters may question why Mr. Obama attached himself to Mr. Wright in the first place and stuck with him for so long, not only attending his church but naming a book after one of his sermons.
Because of his own emphasis on powerful oratory, said Todd Harris, a Republican strategist, Mr. Obama cannot dismiss Mr. Wright?s words as mere rhetoric.
?At the core of the campaign is the fact that words matter,? said Mr. Harris, who is not now affiliated with any campaign. ?Central to the idea of his candidacy is the idea that a speech can change the world. You can?t have a campaign that has that notion at its core and then point to other people?s words and say, those don?t really matter.?
Asked how Republicans might use the Wright matter in the general election, Mr. Harris cited several incidents that could be used to question Mr. Obama?s patriotism. ?Negative ads are built on negative patterns,? he said.
He pointed to Mr. Obama decision to stop wearing a American flag lapel pin and the statement that his wife made about being proud of her country for the first time in her lifetime. (Mr. Obama has called the lapel pin an empty symbol of patriotism, and Mrs. Obama has said she was quoted out of context).
Five weeks before the Pennsylvania primary, Mr. Obama had hoped to be refining his strategy to win over the support of white male voters ? a demographic that began to slip away in his Ohio defeat. Instead he is facing his second straight week of negative news coverage. In a television interview with PBS on Monday, Mr. Obama called his pastor?s remarks ?stupid? and conceded, ?it has been a distraction from the core message of our campaign.?
If his earlier appearances in the day were any guide, he is making a few subtle alterations to his routine on the campaign trail.
In his many months of stumping, Mr. Obama has rarely bid farewell to an audience the way he did at a morning event in Monaca, Pa. ?God bless you and God bless America!? he proclaimed.