If you're an African-American considering a run for the White House in 2016, you've probably already sewn up Rihanna's vote.

Rihanna went on a tour of the White House Monday ... pretending to be the press secretary or a character from "Scandal."

On her way out, our photog asked what the best part of her White House visit was ... and her answer was all about race.

It's been nearly six years since Obama took office, hasn't the novelty worn off?