Marxism is just a clunky ideology rationalizing violence to gain power (and take other people's stuff without paying for it). This is always about raw, naked power.
Some facts:
You can't win the Presidency without winning a significant segment of the South.
The South is a relatively homogeneous culture, apart from the racial divides: rural, agrarian, un-urban.
But after the Civil Rights Act, and the War on Poverty, the enfranchised black populations became a political force. A force that could be used to dominate politics at the local and national level. Whomever controlled the African American population in the South controlled who got the presidency, if the machine could turn the voters out . . . and keep the black population from both assimilating and from achieving enough economic clout to challenge the political order. The corrupt African American establishment the DNC uses to control the process is there to continue, purposefully, enforcing the poverty of African Americans. Meanwhile the existential threat of the KKK keeps blacks both scared and unified.
Therefore, Hillary knows from her experience that keeping blacks both poor and disassociated from their white neighbors is essential to controlling their votes.
Trump's approach to the situation isn't racist. It's the Dem's cynical control over the African American population that's racist.