From the Field summary:

For the first time in over three decades of polling on the issue of same-sex marriage laws, The Field Poll finds more California voters approving than disapproving of allowing same-sex couples the right to marry and having regular marriage laws apply to them. In a survey completed May 17-26 among a random sample of 1,052 registered voters the idea of allowing gay and lesbian couples to marry is now approved by a 51% to 42% margin statewide.

This is up from 44%-50% (with the 50% disapproving) in 2006, and similar numbers in 2003 and 2004. Women are substantially more likely to support recognizing same-sex marriage than men; men favor recognizing same-sex marriage by 4% (within the margin of error), while women favor it by 14%. The proposed constitutional amendment banning recognition of same-sex marriages is opposed by 54%-40% or 51%-43%, depending on how the question is asked. All in all, very different results from those reported by the L.A. Times poll last week.

Note, though, that if civil unions are included as an option, the result becomes 51% to 45% against recognizing same-sex marriage (though that's down from 60% to 36% two years ago).