California Democratic Party Endorses IRV
The 2008 platform of the California Democratic Party says this under Political Reform:

California Democrats believe that a healthy democracy is based on clean elections: public financing of political campaigns at all levels of government, campaign spending limits, restoration of the fairness
doctrine and a strong role for political parties. We will fight the culture of corruption, cronyism and incompetence in politics that has inflicted a great cost upon the American people. We demand open and
fraud-free elections and incontrovertible government accountability to the electorate. We will ensure that all eligible voters can vote, that all votes are counted as cast and can be verified by the voter. We
support public ownership of all election processes, software and equipment. We will insist that officeholders respond honestly and effectively to constituent needs through transparent and open public service.

To promote honest leadership and open government, California Democrats will:

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Encourage, where feasible, instant run-off elections, especially in primaries