Former Housing Secretary Julián Castro, who dropped out of the 2020 Democratic race last week, endorsed Sen. Elizabeth Warren for president on Monday.

“There’s one candidate I can see who’s unafraid to fight like hell to make sure America’s promise will be there for everyone ― who will make sure that no matter where you live in America or where your family came from in the world, you have a path to opportunity, too,” Castro said in a video endorsement.

“That’s why I’m proud to endorse Elizabeth Warren for president,” he added.

Castro dropped out of the race on Jan. 2, to the dismay of some Democrats who thought he was one of the few candidates speaking on behalf of people of color.

Castro and Warren offered similar policy proposals. Both back a form of Medicare for All and advocated the need for racial justice.

Throughout his campaign, Castro sought to appeal to the Democratic Party’s progressive members, routinely criticizing front-runner Joe Biden for policies Castro deemed harmful to Americans. Castro served with Biden in the Obama administration, but he often differentiated his political stances from Biden’s.

“Barack Obama’s vision was not to leave 10 million people uncovered,” by health insurance, Castro told Biden during a debate in September. “He wanted every single person in this country covered. My plan would do that. Your plan would not.”

But Castro’s campaign failed to gain traction. In the waning weeks of his campaign, Castro voiced his concerns about the lack of diversity in the Democratic field.

“What we’re staring at is a DNC debate stage with no people of color on it,” Castro said ahead of the debate.

“That does not reflect the diversity of our party or our country. We need to do better than that.”

CORRECTION: A previous version incorrectly stated all of the participants in the December Democratic debate were white. Andrew Yang, who is Asian American, also participated.