A group backing Democratic scientists running for office is launching a mail campaign to boost stem cell researcher Hans Keirstead ahead of California’s June 5 primary.

314 Action will spend $280,000 on a mail campaign to educate voters about Keirstead, a neuroscientist and CEO of a biomedical company, according to an announcement provided first to Roll Call. The mailers will drop eight times throughout May and target more than 57,000 likely voters. The campaign will also attack Realtor Harley Rouda, one of the other top Democrats in the race.

314 Action has shown a willingness to play in Democratic primaries, reserving airtime in February in several media markets.

Keirstead is in a crowded primary to take on GOP Rep. Dana Rohrabacher, who represents the 48th District in Southern California. Hillary Clinton carried the Orange County district by 2 points. Inside Elections rates the race Tilt Republican. 

This district is one of a handful in the Golden State where Democrats are concerned about being shut out of the November ballot.

In California, the top two vote getters advance to the November election, regardless of party affiliation. So with multiple candidates splitting the Democratic vote, two Republicans could advance to the general election.

That’s a possibility in the 48th District, especially since Republican Scott Baugh joined the race. Baugh is a former state legislator and Orange County GOP chairman.

314 Action also released polling Tuesday showing Keirstead and Baugh battling for second place in the primary behind Rohrabacher. The poll, conducted by Change research, surveyed 590 registered voters online from May 2nd to May 3rd.

The initial matchup showed Rohrabacher garnering 27 percent, Keirstead at 19 percent, Baugh at 17 percent and Rouda at 11 percent. Omar Siddiqui, a former Republican who worked for the FBI, was at 4 percent. The poll had a 4 point margin of error. 

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