According to this article from Huff Post, Donald Trump has been accused of racism in part due to "racially tinged political comments made about President Obama" and his "race-baiting" treatment of African-American contestants on his show Celebrity Apprentice. In an interview this morning on Fox & Friends, Trump had this to say in his defense:

"I am the least racist person there is," asserted the potential presidential contender. "And I think most people who know me would tell you that. I am the least racist, I’ve had great relationships."