The contest was viewed by Democrats as a key part of their attempt to regain a supermajority in the Senate this year.
The contest is to fill a vacancy in the 34th Senate District because term limits prevented incumbent Democratic Sen.
of Santa Ana from seeking reelection.
Nguyen is a member of the Orange County Board of Supervisors and received 51.5% of the vote, according to the unofficial final tally on election night. Solorio received 34% and Republican Long Pham finished third with 14.5%. He is a former Orange County education board member.
To regain a two-thirds majority, Democrats have to win 13 of the 20 Senate seats on the ballot in the November general election.