When pressed to elaborate on his statements, Johnson said he was not targeting Obama's drug use, but his days as a community organizer in Chicago.

"My comments today were referring to Barack Obama's time spent as a community organizer, and nothing else. Any other suggestion is simply irresponsible and incorrect. When Hillary Clinton was in her twenties she worked to provide protections for abused and battered children and helped ensure that children with disabilities could attend public school. That results oriented leadership — even as a young person — is the reason I am supporting Hillary Clinton."

The war of words between the Clinton and Obama camps turned towards race this weekend—which may have prompted Johnson to say what he said—after Clinton commented on Martin Luther King, Jr. and the Civil Rights Movement.

"Dr. King had been on the front lines. He had been leading a movement," Clinton said last Sunday on Meet the Press. "But Dr. King understood, which is why he made it very clear, that there has to be a coming to terms of our country politically in order to make the changes that would last for generations beyond the iconic, extraordinary speeches that he gave. That's why he campaigned for Lyndon Johnson in 1964. That's why he was there when those great pieces of legislation were passed."

Clinton quickly elaborated on her comment. "Does [King] deserve the lion's share of the credit for moving our country and moving our political process? Yes, he does. But he also had partners who were in the political system."

The comment angered some in the black community and many viewed the statement as Clinton trying to diminish the role King played in fight for equality in the country.

"Senator Clinton made an unfortunate remark, an ill-advised remark, about King and Lyndon Johnson. I didn't make the statement," Obama said when asked if he was personally offended by Clinton's comments. "I haven't remarked on it. And she, I think, offended some folks who felt that somehow diminished King's role in bringing about the Civil Rights Act. She is free to explain that. But the notion that somehow this is our doing is ludicrous."

The issue of Hip Hop music and lyrics have also surfaced in this campaign, with Obama's camp coming under fire for the use of a Jay-Z song.

During Obama's victory party in Iowa, Jay's "99 Problems" was played over the loud speaker. Some imply that the line "99 problems but a bitch ain't one" was a thinly veiled shot at his political rival.

The Clinton camp says they "didn't know" Obama used the song and Obama says he is a fan of rap music, dismissing the notion that the song selection was aimed at his political rival.

"I tell you what, I can tell you the kinds of stuff I love dancing to . . . I'm sort of the generation of Stevie Wonder and Earth Wind & Fire," he said in an interview with CNN. "But I'm sort of hip to the younger stuff. You know, like Beyoncé's 'Crazy in Love.' That's a good song to dance to. Eminem . . . although he curses sometimes."