Can I sue for wrongful termination?

I was fired from a large retail chain store for not signing up enough people for credit cards. There was no problem with any other aspect of my job performance. However, me and another female employee were the only ones ever disciplined for the credit compliance and the only ones fired for it, even though statistically we signed up more people than other male employees. I feel like we are being discriminated against. Do I have grounds to sue the company for wrongful termination?