California voters have twice rejected initiatives requiring that parents be notified before a minor can get an abortion, but supporters think the third time might be the charm this Election Day.

Proponents of Proposition 4, which is favored in polls by 8 percentage points, think a key change to the measure will propel it to victory.

"We put in a provision that said if a girl tells the doctor that she has been the victim of abuse by a parent then he can notify another adult family member — a grandparent, an aunt, an adult sibling," said Katie Short, co-author of Proposition 4.

But another factor driving the possible success of the initiative is the influence of Latino voters, who primarily are Catholic and strongly anti-abortion.

"We're expecting a very big turnout this year because of the presidential election, and Latinos, who comprise about 20 percent of the state's voters, will probably be there in force. And if they're 2-to-1 in force then they're probably going to have a big impact on the election," said Mark DiCamillo, director of the Field Poll, a non-partisan California public opinion service.

The measure requires that if a minor requests an abortion, a doctor must send a letter notifying her parent or guardian — but does not require parental consent for the procedure. Forty-eight hours after the letter is sent the girl may have the abortion. Still, opponents call it dangerous.

"The problem is that scared and desperate teens, who for whatever reason can't go to their parents or won't go to their parents, will do dangerous things to themselves," said Mary-Jane Wagle, president and CEO of Planned Parenthood Los Angeles.

Another concern of critics is that if a young woman claims parental abuse to avoid parental notification, doctors must report that abuse to child protective services.

Others doubt whether 48 hours is long enough for delivery of the notification letter. But supporters say their proposition does nothing to change Roe v. Wade — it's simply one way to alert parents their minor daughter may be having an abortion.