I don't have a large working concept of genetics but what I understand is that around 75% or more of orange cats are male.
Some colors in cats are sex-linked, so depending on if you're XY (male) or XX (female) can play on their colors. From what I've read orange is linked to the X chromosome, males have a better chance of getting orange, since females would need both X chromosomes to be orange where a male would only need - only only has - the one.
Now, what I've never understood is if black is also sex linked (as seen with tortties and calicos; you don't get male calicos because both black and orange are X chromosomes so males would need two X chromosomes for this to work; XXY, they'd be sterile)... then shouldn't black cats be more male than female as well? This is something I've never heard discussed.