On June 7, most eyes will be on California's Democratic presidential primary, where Hillary Clinton is set to clinch the delegates necessary for the nomination, regardless of the final margin against Bernie Sanders. But the real action will be in down-ballot races, where June results in a handful of districts could provide clues about candidates' November viability - particularly Democrats' ability to stretch their 39-14 seat advantage. California's top-two primary system - first instituted in 2012 - can produce occasional surprises. All congressional candidates, regardless of party, run on the same June ballot and the top two finishers advance to the November election. In 2012, Republicans claimed both top slots in California's 31st CD when four Democrats split their party's votes, effectively handing Republicans the seat (Democrats won it back in 2014). House Democrats are hoping to avoid the same fate in Santa Barbara's open 24th District this year, where four Democrats and three Republicans on the ballot. For good measure, the DCCC and their allies at the House Majority PAC have spent over $500,000 to boost Santa Barbara County

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