Michael Allen and Marc Levine will compete in an all-Democrat runoff for the 10th Assembly seat in November.
The pair were the leaders throughout the Tuesday night ballot count in the race for the newly created district representing Marin County and parts of Sonoma County.
Of seven candidates Allen received 30.3 percent followed by Levine with 24.2 percent.
In third, with 21.4 percent of the vote, was Peter Mancus, the sole Republican in the race. He is a Sebastopol attorney and gun advocate.
The top two candidates, regardless of party, face a runoff in the general election in November.