As far as I can tell there's not a clear #ProPalestine candidate. Steyer called AIPAC a "dark money organization", but I'm not sure being anti-AIPAC is the same as being pro-Palestine. I can't see any who have used the G word or who endorse economic pressure on Israel. At the same time, it's a state position, not a federal one, so I'm probably not going to hold it as a litmus test.