Not knowing the degree, here is what I would try in order:
- Mr. Clean Magic Erasers.
- Softscrub with Bleach.
- Cleaner / Wax liquid or paste.
- Collinite Cleaner.
- Dupont #7 cut with water (25% water and 75% #7).
- Dupont #7 straight out of can.
Hopefully one of these will work. Be sure to wax after if not non skid. If non skid, maybe Woody's Wax.