Younger voters turned out in surprisingly high numbers on Nov. 6, but they didn't spell victory or defeat for Proposition 30 or other key ballot issues, according to the director of the Field Poll.

"It helped the margin of victory, but it didn't change the outcome," Mark DiCamillo said Thursday of a surge in balloting by voters ages 18 to 29 that bolstered support for the Proposition 30 tax measure.

DiCamillo estimated that the unexpectedly large youth vote raised the Proposition 30 tally by about four percentage points, but the measure won by nearly nine percentage points.

DiCamillo and Mark Baldassare, head of the Public Policy Institute of California, dissected election results Thursday at a session of the Sacramento Press Club.

Even more significant than the youth vote was the impact of minority voters. They turned out in record numbers and tended to oppose Republican positions, the duo said.

"I think the 2012 election in California may prove to be a turning point in California politics," DiCamillo said of the significance of Latino, Asian American, African American and other minority voters, who cast about four of every 10 ballots statewide.

The trend appears to be a bad omen for the GOP, because the party's position on same-sex marriage makes it difficult to attract youth voters and its position on immigration reform repels many Latino voters, Baldassare said.

The full force of the minority vote was demonstrated by President Barack Obama's tally in California: He won by 21 percentage points, yet exit polls showed Mitt Romney was favored by eight percentage points among white, non-Hispanic voters, DiCamillo said.

"This means that Obama owes his entire, not insignificant, huge victory in California to the turnout and the voting preferences of the state's ethnic population," he said.

While younger voters cast a smaller percentage of total ballots than ethnic minorities did, their turnout shocked pollsters nonetheless.

A Field Poll released on Election Day predicted that younger voters would cast about 13 percent of California's ballots. The final number probably will be about 20 percent, DiCamillo said. Field Poll underestimated the youth vote, in part, because it did not capture a surge in voter interest and participation sparked by Gov. Jerry Brown's campaigning on college campuses and by the state's launching of an online voter registration system weeks before the Nov. 6 election, DiCamillo said.

"I think Brown was very effective in the final two weeks at bringing out ethnic voters and younger voters," DiCamillo said.

More than a million new voters registered in the final weeks of campaigning, including 590,788 people who used the new online system, records show.

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