What is the area you would rest your elbow on made of? I have some sort of red stain I can't seem to fully remove. Used a Wolfgang product. No luck.

 

I think it's a vinyl. I would try blueMagic carpet Stain & Spot lifter. Spray it on a towel and rub gently. Becaureful because the stuff is pretty potent and could take some color off. I've never used it on vinyl, but it works awesome on carpet and seat stains. It takes marker and dye out with no problems. Been using the stuff for over 10yrs.