The campaign of Julián Castro, the only Latino vying for the Democratic presidential nomination, announced in an email Monday that he will be forced to drop out of the race if he does not raise $800,000 during the next 10 days.

Castro’s campaign has not met the polling requirement to qualify for the Democratic debate on Nov. 20. He's now at risk of not having the resources needed to sustain his campaign.

“Our campaign is facing its biggest challenge yet,” said campaign manager Maya Rupert in an email to the press. “Secretary Castro has run a historic campaign that has changed the nature of the 2020 election and pushed the Democratic Party on a number of big ideas. Unfortunately, we do not see a path to victory that doesn't include making the November debate stage — and without a significant uptick in our fundraising, we cannot make that debate."

Castro, a former housing secretary under the Obama administration and mayor of San Antonio, has struggled to gain traction in polls and his campaign has little cash on hand compared to other candidates. At the end of September, Castro’s campaign reported $672,333 cash on hand, according to FEC filings. He had raised over $3.4 million during the third fundraising quarter. Castro is not accepting money from PACs or lobbyists.

Some of the higher polling candidates have millions of dollars on hand. And unlike those who hold office, like Sens. Bernie Sanders and Elizabeth Warren, Castro is not able to transfer money from a previous campaign chest.

Just one month ago, Sen. Cory Booker’s campaign announced he had to raise nearly $2 million in 10 days or he had no “legitimate long-term path forward.” Booker eventually reached the goal, which was higher than Castro’s.

It’s not the first time Castro has announced that the end of his campaign could be near. In late September he wrote in an email to supporters: “If I don’t make the next debate stage, it will be the end of my campaign.”

Castro will be in Iowa later this week, for a criminal justice town hall before announcing his criminal justice policy.

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