The Santa Clarita event was sponsored by CHIRLA, the Coalition for Humane Immigrant Rights.
Appearing at the event were three current Democratic members of the House who are eyeing Feinstein's seat - Adam Schiff, Katie Porter and Barbara Lee.
"I don't want anyone to be turned away from access to health care because they're afraid if they try to get access, they might be deported," said Schiff, D-Burbank. "I don't want anyone who seeks to get a better education to be denied that opportunity because of their status."
All three expressed support for immigrants and ensuring access to services and a pathway to citizenship for those seeking asylum.
"Our economy cannot thrive without the contributions of immigrants," said Porter, D-Irvine. "Both those with and without status. Every immigrant family contains hardworking, amazing, talented, dedicated people and every American needs to recognize that we all thrive when our economy thrives."
The latest poll shows Porter and Schiff neck and neck. Former Dodger Steve Garvey who recently entered the race as a Republican, is a point ahead of Lee.
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Lee, D-Oakland said one priority is "making sure that full citizenship is attained, that immigrants get health care and housing and good schools and all of the support that you deserve are available to you."
The primary is March 5, 2024 and the general election is Nov. 5, 2024.
Gov. Gavin Newsom appointed Laphonza Butler to the Senate seat after Feinstein died on Sept. 29. Butler has declared she does not plan to run for a full term in 2024.