Walter:  You don't use the "term Democratic Party guilt (I coined that phrase).  You use the concept "The ugly history of racism and slavery in the Democratic Party is the stink of death, one in which I hope will never, never, ever leave them or give them peace." That, my friend, is the concept of guilt for the "sins of the father."  In regards to history....the written history is there.  The interview with Lee Atwater, the architect of the "southern strategy" is easily Googled.  

Here's a little tidbit from the W.P. "Research has shown that voters who favor Republicans are more likely to hold racial biases against people of color. For instance, nearly one in five Republicans opposes interracial dating, compared to just one in 20 Democrats, according to the Pew Research Center."  So, please, let's not pretend that racists are not far more prevalently Republicans.  Be happy to discuss the issue with you anytime.  Gary Crum