Anti-discrimination laws protect both black and white employees equally. Regardless of your race, an employer many not use any system that incorporates race as a factor in ranking its employees in the receipt of an account. The laws implicated in a discriminatory action are Title VII of the Civil Rights Act (which makes it illegal to alter the terms and conditions of your employment based on you race) and 42 U.S.C. Section 1981 (which says that its illegal to refuse to form a contract due to race).
However, just because all races are to be treated equally under the law, does not mean that there is a clear answer to your question. I would need to know what you mean by "forced ranking." If that is a performance metric, then you may only have a claim if the formula has an adverse impact on one race in favor of another. If is simply based on performance with non racial bias, then the employer may use it.
If a forced ranking is a seniority system, again, this would not be discrimination because seniority is a bona fide consideration for an employer to use to make job assignments.
Depending on how this forced ranking is done you could have a claim under Title VII of the Civil Rights Act of 1964 for racial discrimination. What might seem like minorities are getting better leads might be based on chance or region or a multitude of analytics.
If you truly feel that it is based on ethnicity or race you should bring your concerns to your human resources to see what can be done. It may be one person who is discriminating and they can fix the problem. They may however, fire you in response to bringing it to light. It really depends on the company. They may even show you how everything is done and show you there is no favoritism.
As a past sales and marketing manager usually your favoritism for the best leads goes to the best closers regardless of race or ethnicity as I make my money when sales happen.
Consult your HR first then report back what their response is before I can tell you if you need to hire an attorney.