His point, if taken in context, states that African-Americans and Hispanics vote as a bloc whereas white voters do not. Paul's point is hardly racist; political scientists would verify the truthfulness of the statement. He could have more helpfully quoted a political scientist to that effect but his aim was to tie in the politics of identity with economic issues: much more importantly the concerns of Paul. He continues in the article to discuss the political and economic consequences of identity politics.
The evidence of Paul's racism exists only in the minds of those who have pre-judged him, wrongfully identify him as left of Obama, or misidentify him as a conservative. Paul is an economic libertarian which places him outside the scope of those who promote identity politics or from having an extensive social agenda. He does not. He argues for limited government intervention and would allow the market to decide social issues. Race or identity politics is not his forte. Paul is not a racist.