The Trump campaign has been littered with offensive statements regarding various minority groups. It will be difficult for Donald Trump, at this late stage, to attract any minority group support. He has insulted women, Hispanics and gays, to name a few, and continues to push for more attention. Hillary Clinton has not shown any racial discrimination or bigotry over her career.
Calling someone names will not attract more minorities to him. His actions speak much louder than his words, and his actions have been anything but kind and considerate of minorities in the United States. Simply calling someone else a bigot will not suddenly undo all the things he has said and done.
No, Trump cannot win the favor of minorities by accusing Hillary Clinton of bigotry. Trump has expressed many sentiments that are bigoted or unsympathetic towards minorities, and he will not be able to deflect from this by suggesting that Clinton is bigoted. The only people who will respond positively to this line of attack are those who already support him.
Trump knows he has no chance of appealing to minorities after spending so long going after them, so it's a mystery as to what he is trying to accomplish. The only thing that makes sense is that he's trying to lose and is trying to set himself up as the victim after the election for his fascist media empire.