When I first saw it, I had the same instinctive reaction as you: why is she all of a sudden Asian when she has never explicitly said she identifies as Asian or at least gave the impression that she is of Asian background/decent? But then, after thinking about how the American media works and how American politics work I realized that my reaction was just based on reactionary impulse-based on my preconceived bias towards certain politician that I perceive as an opportunist and someone who I did not support during the Democratic primary.