(Agencies)
Updated: 2008-03-18 16:04

PHILADELPHIA -- Democrat Barack Obama is seeking to distance himself from statements by his longtime pastor that have aggravated racial divisions in the contentious Democratic primary battle. He is calling for both sides to tone down their rhetoric.

US Democratic presidential candidate Senator Barack Obama (D-IL) speaks during a town hall meeting at the Community College of Beaver County in Monaca, Pennsylvania March 17, 2008.  [Agencies]

The Illinois senator is using a speech at a site near the nation's birthplace to present what his campaign said would be a comprehensive take on "race, politics, and unifying our country."

Among other things, the Illinois Democrat was seeking to calm the uproar over racially tinged sermons by his former pastor at Chicago's Trinity United Church of Christ, Rev. Jeremiah Wright, remarks that have threatened to undercut Obama's campaign theme of easing the racial divide.

Wright had been Obama's pastor for nearly 20 years until retiring recently, and officiated at Obama's wedding and baptized his two daughters. His inflammatory statements have been cited by Obama detractors, including comments that blacks continue to be mistreated by whites and a suggestion that US "terrorism" helped bring on the September 11 attacks.

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Obama was addressing supporters at the National Constitution Center, a museum dedicated to the US Constitution.

Jen Psaki, an Obama spokeswoman, said that Obama wanted to deliver the speech because "the issue of race has received an enormous amount of attention" over the past few weeks and "he thought it was an appropriate moment to discuss his thoughts on the issue."

Obama, seeking to be the first black US president, has been calling on Democrats to look past racial divisions and to guard against intemperate rhetoric that he says has been sprouting on both sides.

These include Wright's fiery comments and a recent statement by former Democratic vice presidential nominee Geraldine Ferraro, a Clinton supporter and fundraiser, suggesting he had gotten so far mainly because he was black. "If Obama was a white man, he would not be in this position," Ferraro said in an interview with a California newspaper.

Obama last week called on the Clinton campaign to repudiate the remarks as "a perpetration of the same divisive politics that has done us so much damage." Ferraro later stepped down as a member of an advisory panel to Clinton after Clinton said she did not agree with her remarks.

Earlier, a top Obama foreign-policy adviser, Samantha Power, was forced to step down after calling Clinton a "monster" in an interview with a Scottish newspaper.

Obama, in a speech in Indiana on Saturday, decried "the forces of division" over race and gender that he said were intruding into the Democratic nomination contest.

"We've got a tragic history when it comes to race in this country. We've got a lot of pent-up anger and bitterness and misunderstanding. ... This country wants to move beyond these kinds of things," Obama said.