"Whatever happens in November, what if all Democrats pledged that no white guys will run for president next cycle?" she tweeted on Monday.
She also pushed back on people who wanted Democrats to choose the "best" candidate.
"And yeah we all want the best candidates to run, but if that's your immediate response here, you're kind of telling on yourself that you don't think there are plenty of excellent candidates who aren't white guys," she said.
Her comments came just before Super Tuesday, where the field in which the major candidates are all white and competing for the Democratic nomination. The 2020 field's diversity became a hot topic after Sen. Kamala Harris, D-Calif., dropped out in December, leaving a debate stage with businessman Andrew Yang as the only person of color.
"It's both an honor and a disappointment to be the lone candidate of color on the stage tonight," Yang said during the debate. Sen. Elizabeth Warren, D-Mass., is the only viable female candidate left in the field after Sen. Amy Klobuchar, D-Minn., dropped out of the race.
"It's a sad state of affairs to have six white candidates on stage, many of whom don't necessarily speak with black women, who are the powerhouse voters -- and we're at this moment where we went from the most diverse set of candidates in the history -- certainly in my lifetime -- to an all-white stage," Aimee Allison told MSNBC's Ali Velshi.
Before the Democratic race started, CNN's Alisyn Camerota asked Colorado Governor John Hickenlooper if it was the "right" time for him to run as a white guy.
“But as a white guy, are you trying to calculate whether or not this is the right time for you?” Camerota asked.