San Diego businessman John Cox, the top Republican in the Democrat-heavy field of California gubernatorial candidates, is within striking distance of second place and could proceed to the general election.

Cox will need to finish ahead of former Los Angeles mayor Antonio Villaraigosa in the June 5 primary. Both are battling for second place  after Lt. Gov. Gavin Newsom, the leading Democrat for the Golden State’s highest post.

According to Daily Breeze, an online Eyewitness News/Southern California News Group poll conducted by Survey USA and released Tuesday indicates that Newsom and Villaraigosa are leading with 21 and 18 percentage points respectively, and Cox has 15 percent support.

Republican Assemblyman Travis Allen (R-Huntington Beach) has 10 percent, and Democrat State Treasurer John Chiang has 9 percent.

The poll reportedly also found that 17 percent of voters are still undecided.

Newsom, the former mayor of San Francisco, reportedly has support from many unions, self-described liberals, and suburban residents with higher education.

Villaraigosa, who is of Mexican descent, has the support of the Latino community and tends to draw more from lower-income residents and women, while Cox reportedly has the support of white, conservatives and men.

In March, a poll from the nonpartisan Public Policy Institute of California (PPIC) showed Cox in second place with 14 percent support among likely voters. That same poll showed Newsom with 28 percent support and Villaraigosa with 12 percent support among likely voters.

The California governor’s race has also turned into a proxy war between teachers’ unions and activists who back charter schools.

Netflix co-founder and Chief Executive Reed Hastings reportedly donated $7 million to Villaraigosa’s struggling campaign, and L.A. developer and philanthropist Eli Broad reportedly donated an additional $1.5 million to his campaign. Both men support charter schools.

Meanwhile, Cox has poured $4 million of his own money into his campaign, and has already has spent over $1.5 million on ads throughout California.

Adelle Nazarian is a politics and national security reporter for Breitbart News. Follow her on Facebook and Twitter.