Consider Indians. They are now the highest-income ethnicity in the country - and their Democrat/Republican ratio is roughly 4:1. Accusing them of voting Democratic out of crude self-interest is plainly absurd. In terms of values and family structure, moreover, Indians make most Americans look like a bunch of hippies. Why then do Indians vote like Hispanics?
I'm open to alternative stories, but I think my Respect Motive story fits the facts quite nicely. Indians vote Democratic because they correctly sense that Democrats respect them more. When the typical Republican see women in saris or statues of Ganesha, or hears about arranged marriages and great Indian restaurants, they react less positively than the typical Democrat does.