SACRAMENTO  (AP) — Nearly two-thirds of California voters cast their vote by mail in the June election, a record for the state, but fewer than a third of registered voters turned out, Secretary of State Debra Bowen reported Friday.

Bowen's office officially certified the results of the primary election, which was the first time Californians tested two new voter-approved changes: a top-two primary system and new congressional and legislative boundaries drawn for the first time by an independent commission.

The new primary system led to a crowded ballot in many races; U.S. Sen. Dianne Feinstein faced 24 challengers. She faces Republican Elizabeth Emken in November.

Bowen reported that only 31 percent of the state's registered voters, or about 5.3 million people, turned out. The figure is low, but still slightly higher than the 28 percent record low turnout in June 2008.

Sierra, Alpine and Amador counties had the highest turnout as percentage of registered voters, while San Bernardino, Orange and Los Angeles counties had the lowest turnout.

Bowen's office also reports that voters rejected a proposed $1-a-pack tax on cigarettes to pay for cancer research by a slim margin of 24,076 votes. That measure, Proposition 29, remained too-close-to call for weeks, but campaign supporters conceded defeat on June 22.

A San Francisco surgeon who supported the tobacco tax on Thursday requested a recount of ballots in 190 Los Angeles County precincts in the Sherman Oaks and North Hollywood areas. Those precincts accounted for about 48,000 votes cast June 5.

Los Angeles registrar Dean Logan said the recount will begin Monday with an electronic tally before a manual count at midweek.

Voters in June mostly rejected the independent and moderate candidates that the electoral changes were intended to bolster to reduce partisanship, instead sending every state legislative and congressional incumbent forward to runoffs in November, in some cases against opponents in their own party.

Voters will also be asked to decide on 11 ballot measures, including a proposed sales and income tax increase backed by Gov. Jerry Brown, a Democrat, a competing measure that would raise income taxes to fund schools, a proposal to repeal the death penalty and a so-called "paycheck protection" measure that would restrict unions and other groups from using members' dues for political campaigns.

That election also includes the presidential race, and is likely to generate higher turnout than June's.