Presidential candidate Elizabeth Warren told a crowd of supporters in Iowa that her potential secretary of education would be "someone who's taught in a public school" and that the nominee would also need to be vetted by a "young trans person."

"I'm going to have a Secretary of Education that this young trans person interviews on my behalf, and only if this person believes that our Secretary or Secretary of Education nominee is absolutely committed to creating a welcoming environment, a safe environment, and a full educational curriculum for everyone will that person actually be advanced to be Secretary of Education."

Warren appeared to be referring to Jacob, a 9-year-old transgender boy that she spoke with during a CNN presidential candidate forum on gay and transgender issues in October 2019.

Warren, 70, has seen her poll numbers drop as the 2020 presidential race nears its first primary in Iowa on Feb. 3. In December, the Massachusetts Democrat pledged to annually read the names of murdered transgender people of color in the Rose Garden if she is elected president.

On Wednesday, Warren proposed a plan to censor "disinformation" on social media platforms.

[Read more: How Warren's ambush of Bernie Sanders backfired]