Oregon reaffirmed its status as a solid abortion-rights state Tuesday, defeating a measure that would have required the parents of underage girls to receive written notification if their daughters were seeking an abortion.

Voters in California defeated a similar parental notification measure, while in South Dakota, an estimated 55 percent of voters defeated a measure that would have outlawed the procedure under almost any circumstances.

With 40 percent of the projected vote counted, 54 percent of Oregon voters had logged "no" votes on Measure 43.

Oregon is among a handful of states nationwide that places virtually no restrictions on the procedure, and both sides in the abortion debate had viewed the race as a must-win.

The measure's opponents were helped by a strong surge of Democratic voters throughout Oregon, and also by a late television ad that was in heavy rotation during the final week of the campaign, implying that parental notification could endanger teen girls.

"Oregon voters saw through this," said Carol Butler, who managed the No on 43 campaign. "Voters decided that they were going to say no to placing vulnerable teens in danger."

The measure's defeat holds wider implications for the anti-abortion rights movement in Oregon. Parental notification is a relatively mild restriction on the procedure -- some states require teens to get written consent from both parents before they can get an abortion -- and its failure makes it somewhat less likely that future proposed restrictions could find favor among Oregon voters.

"I'm just really disappointed that there are a lot of girls left unprotected and traumatized by the status quo right now," said Sarah Nashif, who managed the Yes on 43 campaign.

Noting that the measure was passing in early polls before the other side unleashed a barrage of ads and mailers, she said those who favored the measure were ultimately outspent by money that came from out-of-state abortion-rights groups.