Supporting anyone does not intrinsically make you a racist. However, if you think Trump is a racist, and you vote for him because of this, you are probably a racist. I hope(and suspect) that this is not a common occurrence.
You are cherry picking and are viewing the situation with a very heavy bias. Both sides obstruct the opposition, both sides have engaged in filibustering. The GOP worked to free the slaves and the Democratic party instituted Jim Crow and filled the ranks of the Klan. Picking your favorite color and pointing fingers is not an effective strategy for improving the world around you.
Furthermore, people who disagree with you aren't necessarily bad people. For example, Nobel prize winning economist Milton Friedman advocated against raising the minimum wage, as does economist Thomas Sowell. You may disagree and think the minimum wage should be increased, but that doesn't make those guys evil. In fact, they both thought/think the minimum wage laws hurt the poor. Thomas Sowell even thinks the laws were motivated by racist whites looking to keep blacks unemployed.