If people use evolution to promote racist ideologies, then they either don't understand it, or are deliberately misusing it for their agenda.
"Evolutionists" will readily tell you that races, for all practical purposes, are non-existent. A more accurate way to describe the divisions in humanity is to talk about "haplogroups", which do not necessarily correspond with the physical attributes commonly associated with "race".
For example, Europeans and Native Americans are part of one haplogroup that split from another haplogroup that is represented by the people that entered India from the north (as opposed to the haplogroup that entered India from the coast, parts of which population continued to move east and colonize places like the Philippines and Australia). There is a group in the Sahara that, although possessing black skin and other "african" features, are part of a haplogroup that is mostly represented in the Middle East. So even though they are black and look like most of the rest of the sub-Saharan Africans, they are actually more closely related to those in the Middle East.
"Racism" is not supported by evolution. As mankind spread, certain outward features changed as we went into different environments. Not all of those traits were even necessarily due to the environment. Sometimes people just find certain things attractive. But the number of genes that are required to make those superficial changes are so small that there is essentially no genetic difference between different "races". The difference is just as much as between members of the same "race".
So no, evolution is not racist. People are racist and use a twisted version of evolution to promote their racism.
And for the record, I do not claim to subscribe to common descent, and I take a rather agnostic stance when it comes to the mechanics of life and its development since creation. I just like to see points of view accurately represented.
For a cursory overview:
Haplogroup - Wikipedia, the free encyclopedia