2020 hopeful Castro holds Trump counter rally in San Antonio

Democratic presidential candidate Julian Castro is using President Donald Trump's visit to his hometown as a chance to give a jolt to his own campaign

He ripped Trump's hard-line immigration policies as "downright stupid" and told supporters his campaign stood for compassion.

Castro is still trying to get a foothold in a crowded Democratic field. He says he hasn't yet reached 65,000 donors, which is one of the criteria used to qualify for the first Democratic debates. Candidates can also get on stage by reaching 1 percent approval in three recognized polls.