Taking direct criticism to the woman he is attempting to unseat in next year’s U.S. Senate race, California Senate leader Kevin de León on Wednesday urged Democrats to block a year-end spending bill as leverage to pass a Dream Act — “clean” of GOP demands for increased border security.

At a news conference in downtown Los Angeles, De León commended Sen. Kamala Harris for pledging to block the measure, saying he could not understand why her colleague Sen. Dianne Feinstein had failed to take a similar stance in pushing for legislation to protect the so-called Dreamers, immigrants brought to the country illegally as children.

“Dreamers make up hundreds of thousands of Sen. Feinstein’s constituents, and while talking a good game on Dreamers, when it comes to standing up and supporting them, she is AWOL,” said De León (D-Los Angeles), who has attempted to position himself to Feinstein’s left as he campaigns for her seat.