(CNN) California is set to become the first state to extend health coverage to some undocumented young adults through its Medicaid program.

The move by the big blue state comes as the Trump administration is cracking down on undocumented immigrants, particularly at the southern border -- and as the Supreme Court is poised to take up a case concerning President Donald Trump's moves to undo Obama-era protections for young adults brought to the US as children. But it is also a time when Democrats are seeking a pathway to get more uninsured people covered.

The state legislature, which is dominated by Democrats, agreed Sunday to the provision, which was pushed by Democratic Gov. Gavin Newsom, as part of its broader budget deal. They must vote on it by June 15.

Newsom proposed the effort -- part of a larger health care package -- on his first day in office in January. It is expected to cover more than 90,000 low-income residents between the ages of 19 and 25 and cost the state $98 million in its initial year. The coverage would take effect in 2020.

The Golden State led the way in this arena by covering undocumented children up to age 19. Some 240,000 children are now in the program, which began in 2016.

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