Thank you for your question. I look forward to working with you to provide you the information you are seeking for educational purposes only.
Whether or not you can get an attorney on a contingency fee basis is up to you to negotiate with the attorneys you are seeking to hire. Attorneys decide how to collect fees and it is based on the strength of the case and the determination they make as to whether or not they will be able to ultimately collect from the other party to get their fee if they win the case. So, you will have to interview some attorneys and bring them the evidence you have and they have to evaluate it before deciding to agree to a contingency fee agreement.
As far as appealing your loss of your State Supreme Court decision to the federal courts, generally such decisions are not appealable to the federal courts as a rule. The Rooker-Feldman doctrine states that once you have obtained a final judgment from a state court, you cannot jump to the federal district court
seeking to re-litigate issues that have already been decided at the state level. The courts evaluate your case and Rooker-Feldman applies when the following four factors are present:
1. The plaintiff seeking to bring a claim in federal district court has already lost on that claim in state court;
2. The plaintiff is complaining that the state court judgment caused him some sort of injury or harm;
3. The plaintiff is asking the federal district court to review and overturn the state judgment; and
4. The state court finalized its decision on the claim before the federal district court began its own proceedings.
See: Exxon Mobil Corp. v. Saudi Basic Industries Corp., 544 U.S. 280 (2005).
If you are challenging the constitutionality of the statute applied to your case by the court, then Rooker-Feldman does not bar you from presenting a facial challenge to the constitutionality of a state statute in federal court, even if a state court previously applied that state statute against the plaintiff. You would do so by filing a new complaint in the US District Court challenging the fact that the statute itself was unconstitutional. You cannot simply challenge your case because the State Supreme Court ruled against you in your equal protection case though, you have to challenge it on the basis that the law applied is unconstitutional.