Now that Jerry Brown is in office one might think it would pass, but it's going to be a long haul:
Why Did Single-Payer Health Care Fail in California?
By Lenny Potash
Labor Notes, Feb. 17, 2012
Though its passed the legislature twice before, a bill to establish a single-payer universal health insurance system in California failed in the state senate in January. Not surprisingly, the bill received no Republican votes, but it fell just two votes short of passage when two Democrats voted no and four Democrats failed to vote, despite intense lobbying efforts by community and some labor health care activists.
Angry activists pointed to the fact that five of the six errant Democrats had received money from the insurance industry and Big Pharma, ranging from $100,000 to over $250,000. Three of the six senators had been endorsed by the California Labor Federation which, along with unions such as the Service Employees and AFSCME, was on record supporting the single-payer bill. The California Democratic Party was also on record supporting it. Similar bills passed the legislature fairly easily in 2006 and 2008, only to be vetoed by then-Governor Arnold Schwarzenegger. At a time when premiums were rising and there were few other proposals out there, it was an easy vote for Democrats certain of the governors veto.
But when Congress passed federal health reform in 2010, defending that bill, as well as President Obama, became paramount for many Democrats. It became more difficult for legislators to vote for a single-payer bill that might be interpreted as deserting the president, and the Democratic leadership refused to put the bill up for a final vote in the Assembly.
In 2011-12 the issue in some ways became even more loaded, with a Democratic governor facing massive budget deficits. Even though single payer would save Californians much more money in the medium term by reducing the huge overhead costs of insurance and drug companies, Governor Jerry Brown did not express support for the measure, and some Democrats feared to be seen backing an expensive bill.
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More at the link:
http://www.pnhp.org/news/2012/february/why-did-single-payer-health-care-fail-in-california