goof off is good. if that doesn't work, go to the hardware store and buy some paint thinner and gloves. soak a rag in paint thinner and rub vigorously. you can also wrap a putty knife in a thinner soaked rag and use it to "scrape" away the stain. If that doesn't work, try laquer thinner, it is "hotter" and will activate some things paint thinner won't. Don't be stupid, open windows wear gloves. Also if the bucket paint was latex(water based) then a hot water rag and the putty knife trick should work. cover the floor next time.