If you divide total off court career earnings by pro years, Nadal might be higher. But in gross earnings I think Federer will.
Off the top of my head, Fed endorses Nike, Wilson, Rolex/Lacroix (one or the other), has or continues to endorse Emmi (Suisse yogurt).
And as No.1 I think his appearance fee (also part of off court earnings) would be higher, but that is just a guess.
so only so few products ?? Even Andy Roddick do better : Lacoste, Babolat, Rolex, Powerade , American Express, Lexus , SAP
I am sure Federer endorses much more products