There's got to be a reason I never thought of it before. Andrew Sullivan reports rumors that Louisiana Governor Bobby Jindal may be on John McCain's list of potential VPs. It'd make a great political counter to an Obama candidacy. Jindal's Indian-American, so it isn't an exact parallel (but that makes it easier to dodge the inevitable pandering charge), while still being historic (Indians are a special race case anyway). And it's not like he'd be plucked from complete obscurity -- Jindal's been a GOP rising star for awhile now, and has a good many people in the Party excited.
Americans tend to like it better when Republicans usher in their great progressive leaps forward (cf., Nixon goes to China), because it gives them all the symbolism without the risk that anything substantive will change. It'd be interesting to see how much significance would be ascribed to Jindal's ascension as VP. Obama's potential election as President has led a certain class of White pundits to proclaim it as evidence that anti-Black racism is effectively over. Would Jindal's election still be used to justify the same claim (because Whites have overcome their racial animosity as evidenced by Jindal, ipso facto Whites no longer harbor racist sentiments toward Black people)? It'd be convenient, but still rather difficult I think to argue.