Republican Elizabeth Emken secured a runoff spot in Tuesday's U.S. Senate primary, winning the chance to go head to head with Democratic Sen. Dianne Feinstein in November.
The Danville Republican was one of 23 candidates challenging the longtime Democratic senator on the primary ballot.
Emken led the pack with 12 percent of the vote in the "top two primary" free-for-all that allowed voters to choose among candidates of all political leanings.
Feinstein easily captured the top spot in Tuesday's election, winning 50 percent of votes cast in early returns.
Though her approval ratings have dipped in recent months, Feinstein is considered to have a clear shot at winning a fourth full term this fall. The 78-year-old incumbent has built statewide name identification and a multimillion dollar campaign war chest in her two decades in the U.S. Senate.
Emken, a longtime advocate for children with autism, edged out a field of mostly unknown and underfunded Republican rivals to win the state party's endorsement ahead of the primary.
Republican businessman Dan Hughes, a first-time candidate, came in third with 6 percent of the vote.
The remaining candidates fought for slivers of the vote in early returns, with most of them winning 2 percent or less each of the votes cast.
Orly Taitz, the Laguna Niguel attorney and dentist who is best known for efforts to document her belief that President Barack Obama lied about his birthplace and is not eligible to serve as commander in chief, carried about 3 percent of the vote.
Emken, whose 19-year-old adult son is autistic, has spent the last 15 years working as an advocate focused on the condition.
Her recent work as the vice president for government relations for the national nonprofit Autism Speaks sparked attacks from GOP rivals, who said the nonprofit's work to shape the federal health care overhaul conflicted with Emken's stated opposition to the law.
Emken relied heavily on talk radio appearances and social media to reach voters ahead of Tuesday's low turnout election.
She reported raising about $327,686 in campaign funds by mid May, but entered the final stretch of the race with about $23,669 in cash on hand and more than $200,000 in campaign debt.
This is the second time the Danville Republican has run for office in California. She came in last place in a four-way congressional primary in 2010.
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