A group of liberal Zionists based in Solano County is organizing against what its members see as an effort within the progressive wing of the state Democratic Party to ostracize supporters of Israel. The Progressive Zionists of California announced Jan. 26 that it had launched a petition and letter-writing campaign imploring the state’s Democratic Party leaders to oppose what it called “dangerous litmus tests.” PZC is a three-year-old activist group whose co-founders are residents of Vallejo and Fairfield. The group’s latest actions follow a controversial statement and questionnaire sent out in December by the Progressive Delegates Network to delegate hopefuls. The document focused unduly on the Israel/Palestine conflict, PZC activists said.