A victory by de Leon would be a death knell to the moderate Democratic establishment and a swing to the left in the party. The race is likely to get expensive because under California’s system Feinstein and de Leon will face each other in the June 5 open primary and the general election in November. A fascinating outcome of this race would be that de Leon and Feinstein could split the Democratic vote, and provide an opening for a Republican to reach the Senate from California. Another game-changing factor is Feinstein’s health, she’s 85 and looking increasingly frail, so the Senator might drop out any time.