Why does Grant think that Jefferson is "more than a man" than he is?

Re-edit from last answer. I think Grant almost envies Jefferson as he can die in the name of a black cause. He can die a martyr knowing the injustice done to him was a result pure racism. Grant feels he lives in a world where he is willingly subservient to whites. He sees Jefferson's execution as an act of defiance while he (Grant) validates the racial status quo.