Very few political races can hope to muster three Democrats with a more experienced resume than the trio that will likely face off in the 2016 June primary for the State Senate’s Ninth District. Start with former Oakland Assemblymember Sandré Swanson. After he was termed out in 2012, he served as then-Oakland Mayor Jean Quan’s deputy mayor. Last month, he unofficially kicked off the primary season by announcing pivotal endorsements from the current holder of the seat, State Senator Loni Hancock, and from East Bay Assemblymembers Rob Bonta and Tony Thurmond. Endorsements notwithstanding, another former member of the Assembly, Nancy Skinner, is also a strong contender with longstanding ties to the Berkeley portion of the sprawling district that also includes Oakland, Richmond, Alameda, and San Leandro. And don’t count out Alameda County Supervisor Wilma Chan, who has held elected office longer than both Swanson and Skinner, including a stint as Assembly majority leader more than a decade ago. Don’t expect many policy differences in this group of labor-friendly progressives. And because of the top two open primary system, this race will be less about who wins in June, but which of the three Democrats is left by the wayside.