It's funny how the two major regions of the US that clearly deserve statehood (DC and Puerto Rico) but have been denied that right for decades, seem to be areas with lots of poor non-whites.
Racism is not the only factor in play here (political balance of power is a huge factor), but to deny that racism has played a significant role in creating this situation is ridiculous.
I place that racism squarely in the laps of both parties since they both deserve that blame.