You can dislike or even "hate" Obama w/o being racist. No doubt. But many people who do are indeed racist. They're the people sending around watermelon jokes, calling him and his family monkeys, saying he looks like a skinny ghetto crackhead, claiming he wasn't born here or saying someone should shoot the n******

The modern Republican party won't/can't distance itself from such people which is why it is in danger of becoming an explicitly white nationalist party. In a country that is changing rapidly demographically this could become an increasing problem over the next 3-4 presidential elections.

"When the snows fall and the white winds blow, the lone wolf dies but the pack survives."
Winter is Coming

Now this is the Law of the Jungle—as old and as true as the sky; And the wolf that shall keep it may prosper, but the wolf that shall break it must die.
As the creeper that girdles the tree-trunk, the Law runneth forward and back; For the strength of the Pack is the Wolf, and the strength of the Wolf is the Pack.