It probably doesn't help that his surname isn't easy to pronounce either. My best friend, who doesn't watch any tennis at all, referred to him as 'the guy with the weird surname'.
That said, in my opinion, he is theoretically more marketable than Nadal. 1) He speaks WAY better English; and 2) he's better looking.
True, my friends who do.not follow tennis often mean to ask me how he is doing but they always ask.me for his name, because they never seem to memorize it.
He might be theoretically more marketable. But Rafa Has been around for longer, Has won far more titles and is from Spain.
Nole would have to pull and incredible run in the next 2 or 3 years to become bigger than nadal.in terms.of endorsement. And even then I am not sure.
It's easy to understand really. If you go to a tournament and they are both practising at the same time, Nadal.is going to have a lot.more people watching him than Nole.