• Attitudes toward same-sex marriage shifted in 2010.
  In the January 2013 PPIC Statewide Survey, 53% of Californians favored (and 41% opposed) allowing gay and lesbian couples to legally marry. This 12 point margin of support reflects a relatively recent shift in attitudes toward same-sex marriage. When PPIC first asked this question in January 2000, a majority of Californians (55%) were opposed (39% were in favor). The margin narrowed over the next decade, and in March 2010, for the first time, support reached 50%, while 45% remained opposed.
  
• Same-sex marriage divides Democrats and Republicans, but support has increased among both.
  In November 2008, California voters approved Proposition 8—which amended the state constitution to prohibit same-sex marriage—by a narrow 52% to 48% margin. Although same-sex marriage remains a divisive issue among partisans in PPIC Statewide Surveys, support has increased among both Democrats and Republicans since October 2008, the last PPIC survey conducted before the November 2008 election. Support has grown 11 points among Democrats (from 56% in 2008 to 67% in January 2013) and 7 points among Republicans (from 23% in 2008 to 30% in 2013). Support among independents has inched up slightly (from 53% to 59%).
• Since 2008, support has increased in many demographic groups …
  Older Californians are now closely divided on same-sex marriage (46% favor, 47% oppose) after having opposed it by a 24 point margin in October 2008 (34% in favor, 58% opposed). Support has grown 9 points among younger Californians, age 18–34 (from 53% to 62%). At least half of both women (56%, up from 47% in 2008) and men (50%, up 8 points) now support same-sex marriage. In their 2008 campaign, Proposition 8 proponents appealed to parents by claiming that if same-sex marriage remained legal it would be taught in schools. A majority of parents expressed opposition at the time (42% in favor, 54% opposed), but the opinion gap has since narrowed (47% in favor, 47% opposed). Support for same-sex marriage went from 50% to 56% among whites and increased 12 points among Latinos (from 36% in 2008 to 48% in 2013).
• … and also among Protestants.
  Although 71% of evangelical Protestants remain opposed to same-sex marriage, support has increased 10 points, from 15% in 2008 to 25% in May 2012. A majority of mainline Protestants now favor allowing same-sex marriage after support increased 12 points from 2008 (from 44% to 56%). Support among Catholics is similar to 2008 (42% in 2008, 45% 2012).
• Most Californians consider U.S. Supreme Court decision on Proposition 8 important.
  In February 2012, the U.S. Ninth Circuit Court of Appeals ruled that Proposition 8 is unconstitutional. Proposition 8 proponents appealed the case to the U.S. Supreme Court, which heard arguments on March 26. Nearly two in three Californians say the court’s decision is either very (38%) or somewhat important (26%). Those who oppose same-sex marriage are more likely than those who favor it to say the decision is very important (46% to 36%).
• National organizations and public figures (including the president) have endorsed same-sex marriage.
  In May 2012, Barack Obama became the first sitting president to express support for same-sex marriage. At the time, the president’s endorsement caused 22% of Californians to view him more favorably, 24% to view him less favorably, and 53% to say it did not affect their views. Since then, numerous public figures (including Bill Clinton and Meg Whitman), businesses (including Apple and Microsoft), and organizations (including the American Academy of Pediatrics) have expressed support for gay marriage; many have also filed amicus briefs in support of the couple challenging the constitutionality of Proposition 8.

Source: PPIC Statewide Surveys, January 2000–January 2013. Margin of error for all adults in October 2008 is ±2%, in May 2012 is ±3.6%, and in January 2013 is ±3.5%; margin of error for subgroups is larger.