The roots of the tension are economic and cultural: black voters worry that Latinos are taking their jobs, undercutting their wages, and usurping their political power. The tension creates its own reaction, and is exacerbated by the fact that the Latino population in California is booming while the black population is both more stagnant and increasingly geographically fragmented, as blacks move out of central L.A., San Francisco, and Oakland into the suburbs).
This tension was very visibly on display in the 2007 race to succeed the late Rep. Juanita Millender-McDonald (D-Long Beach), in which a black candidate, Assemblywoman Laura Richardson, and a Latino candidate, Senator Jenny Oropeza, squared off on more or less explicitly racial lines. (Richardson won.) The black establishment in L.A. was vehement that they couldn't afford to lose a "black seat."
The media can oversimplify the tension. Latino candidates, for instance, are certainly capable of winning black votes -- think of Antonio Villaraigosa, now a Clinton endorser, who capitalized reasonably successfully on black dissatisfaction with Mayor Jim Hahn after Hahn dismissed black police chief (now city councilman) Bernard Parks. Villaraigosa apparently got 48% of the black vote in 2005, up 28 points from his unsuccessful run against Hahn in 2001.
A keen analyst of California politics writes:
I also think the media is overstating the degree of Latino solidarity for Hillary Clinton. To my mind, the Clintons aren't unusually beloved by Latinos in California, not the way they are by blacks. (Keep in mind that a healthy minority of Latino voters probably weren't citizens even as recently as the Clinton administration.) Hillary's lead among Latinos is, I suspect, just an artifact of the fact that California voters and Latino voters were until recently paying even less attention to the election than other voters nationally.
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