2010 Democrats: Arnold is an awful evil Republican
2018 Democrats: Anyone who could stick it to Trump is worth a look
2010 Republicans: Arnold is apostate
2018 Republicans: He'd be better than a Democrat. Why not?
I don't think Schwarzenegger could beat Feinstein but he could easily make top two and face off with her in November 2018. If Feinstein were to retire Democrats don't have anyone with a profile like Kamala Harris. Gavin Newsom, John Chiang, and Antonio Villaraigosa could abandon the governor's race but they couldn't transfer their huge war chests. Congressmen like Raul Ruiz or Ami Bera could run but neither has much of a statewide profile. And if Arnold ran as NPP Democrats who won't vote Republican might for him.