Sen. Barack Obama on Saturday decried "the forces of division" over race that he said are intruding into the Democratic presidential nomination contest.
"We have to come together," he told a town-hall meeting at a high school.
He cited videos of inflammatory sermons given by his pastor that are now being used as political ammunition against him — remarks that Obama has denounced.
"If all I knew were those statements I saw on television, I would be shocked," Obama said.
Obama suggested that more and more is being made of racial divisions as his contest with Sen. Hillary Rodham Clinton heats up.
"I noticed over the last several weeks that the forces of division have started to raise their ugly heads again. And I'm not here to cast blame or point fingers because everybody, you know, senses that there's been this shift," Obama said.
"It reminds me: 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."
The Illinois senator's comments came a day after he denounced statements in videos appearing on television and on the Internet of sermons by the Rev. Jeremiah Wright, pastor of the Chicago church Obama joined nearly 20 years ago.
"Most recently, you heard some statements from my former pastor that were incendiary and that I completely reject, although I knew him and know him as somebody in my church who talked to me about Jesus and family and friendships."
Obama said that pointing out racial differences only makes it harder to "deliver on the big issues we face in this country," which he said include health care, the slumping economy, terrorism and caring better for veterans.
Obama, whose mother's family was from Kansas and his father from Kenya, said he was speaking "as someone who has little pieces of America all in me."
He said schools should do a better job of teaching all students African-American history "because that's part of American history," as well as women's struggle for equality, the history of unions, the role of Hispanics in U.S. and other matters that he suggested aren't given enough attention.
"I want us to have a broad-based history" taught in schools, he said, even including more on "the Holocaust as well as other issues of oppression" around the world.
Obama spoke in the gymnasium of Plainfield High School, near Indianapolis, as he directed his political attention at states beyond the critical April 22 Pennsylvania primary.
"We are going to be campaigning actively in Indiana," Obama said to cheers. Indiana and North Carolina have primaries on May 6, two weeks after Pennsylvania.