Immigration and border security issues unify Republican voters while dividing Democratic voters in California, a statewide poll has found.

The findings of the new UC Berkeley Institute of Governmental Studies poll, co-sponsored by the Los Angeles Times, illustrate some of the political difficulties President Biden faces in dealing with the large number of unauthorized migrants crossing the U.S. southern border.

Even in California, a Democratic stronghold, registered voters by 62% to 30% say U.S. borders are not secure in preventing people from entering the country illegally, the poll found. The majority who say the border is not secure is even larger among likely voters.